Desktop Motherboard Standby Voltages, Power Rails, and … — Transcript

[Music] Welcome back to the channel. In the previous video, I've explained which vectors are responsible for the physical size of a modern motherboard. In this video, I will analyze the full power sequence of a modern desktop motherboard. The power sequence in the desktop motherboard refers to the precise order and timing in which power is delivered to the motherboard's different components during startup. Modern desktop motherboards house interconnected components like the CPU, the random access memory, and the chipset, each of which depends on others to function correctly. For instance, the chipset or the PCH often needs to be powered before the CPU because it has to facilitate the communication during the initialization. Also, the random access memory must be operational before the CPU can access it for its first instructions. A precise voltage sequence ensures that these dependencies are met, allowing the system to boot successfully. I don't know if the power sequence can be discussed in one video. If not, I will make a multi-part video. At the end of this course, you will be equipped with enough knowledge to analyze and repair any motherboard. If you gained any value from this guide, consider giving it a like and help me to grow the channel and create more content that you enjoy. And do not forget to subscribe to the channel for more in-depth analysis like this one. So let's start. In this video, I will be analyzing the Z270 Gaming Pro from MSI, which is a 7th generation motherboard. Analyzing this 7th generation motherboard provides a basic understanding of motherboard architecture, component layout, and functionality that can be applied to higher generation motherboards. Understanding the power sequence of the 7th generation motherboard equips you with the framework to anticipate and understand improvements in new generations of motherboards. This knowledge will assist you in troubleshooting different motherboards, and of course, there will be little differences in the power sequence with each new generation motherboard and CPU manufacturer, but the basic information still applies. The Intel Z270 is a high-end chipset. It was introduced in early 2017. It was designed to support 6th generation Skylake and 7th generation Kaby Lake Intel Core processors. The Z270 chipset acts like a central communication hub. It helps the different parts of the computer like the CPU, the memory, storage, and other devices to talk to each other. Think of the chipset as a traffic controller that directs data where it needs to go inside of the computer. The chipset only works with CPUs that the chipset supports. Let's identify the most important components on this Z270 mainboard. This is the CPU, and this chip here is the chipset Z270. I have removed the rectangular heat sink that is above this chipset, so normally it looks like this. On the other side, this is the Super I/O chip. This chip is responsible for managing legacy and low-speed input/output functions that are not handled by the CPU or the chipset itself. This is the feedback circuit, also known as the real-time clock circuit. This RTC circuit tracks time and date continuously, even when the system is powered off. It uses a small 3V battery to maintain its operation independently of the main power supply. So when there is no mains connected, this battery will provide power to generate a real-time clock signal. This is the 24-pin ATX power connector. This connector is the primary power supply connection that delivers electricity from the power supply to the motherboard. When you turn your motherboard on, the power supply will generate different voltages that the motherboard needs. This is the CPU power connector. On one row, it connects to ground, and the other one will get the 12V from the power supply. This power connector will deliver the necessary power to the CPU. These connectors typically come in a form of four pins or eight pins. The power supply for the CPU is separate from the 24-pin ATX power connector because this power connector is designed to handle high current and power demands that this CPU needs. In this region, there is a voltage regulator that will create 3.3 volts. Near the Super I/O, there is a 3.3-volt voltage regulator that will provide power to the Super I/O. Near the chipset, there is a crystal located. This crystal will generate a clock signal of 32 kHz. On the end of the motherboard, there is a voltage regulator that will generate 5 volts. Between these two PCIe slots, there is a voltage regulator that will create 3.3 volts standby. In area 12, there is a voltage regulator located that will generate 1.05 volts for the PCH chip or the chipset. In region 13, there are some voltages generated for the CPU, and these voltages are around 1.1 volts and are needed by the CPU. PCH SD powers the standby logic and parts of the CPU that must remain operational even in low power states like sleep or hibernation. In region 14, you can connect the front panel connectors for the power button. Near the AIO IC, there is a USB controller. This controller is responsible for generating the voltages and data signals from the different USB ports. This voltage regulator will create the power for the USB at the rear side, so the power for the front side USB connectors is generated in this region. In regions 18, 19, 20, and 22, these voltage regulators will create the power for the DDR RAM memory. There are different voltages that the DDR memory needs, and these regulators will create that voltage. In area 23 and 24, these are CPU voltages. One is called VCCIO, and the other is called VCCSA. VCCIO refers to a voltage rail used to power the input and output circuits that are in the CPU. VCCSA stands for voltage for system agent. The system agent is a component inside the CPU that is responsible for different tasks like managing the memory controller, PCIe lanes, integrated graphics, and other input/output subsystems. These two voltage rails are also voltage rails for the CPU. In area 25, we can measure an important signal, the PCH power OK. PCH power OK is a signal generated by the PCH to inform the CPU and the BIOS that this PCH has been properly powered and is fully functional. In area 26, you can find the CPU power good signal. The CPU power good signal is generated by the VRMs or the controller that powers the CPU. It confirms that the CPU has received stable power, including the correct voltage and current, and it is ready to operate without issues. So the power generation for the CPU Vcore is OK, and the signal can be found here between these two sockets and also on some dedicated pins on the RAM slots. There is a signal called DRAM reset. When the system is powered on, the DRAM reset active low signal is pulled low to reset DRAM. This ensures that the memory modules are in a non-cleared state before data is read or written. In this area near the Super I/O, there is a signal called platform reset active low. The hash symbol indicates that it is an active low signal, meaning the reset is triggered when the signal is pulled low to ground. So in every signal that has a hash, it means that the signal is active low when it's pulled to ground. In area 29, we can find the CPU reset active low signal. When the CPU reset signal is pulled low, it forces the CPU into a reset state, actively stopping its current operation and clearing any internal states or registers. This ensures that the CPU starts executing from a known state once the reset is deasserted, so the signal goes back high. In area 30, we can find a CPU PWM controller. This controller will drive the VRMs that will generate the Vcore for the CPU and the graphics core for the CPU. In area 33, we can find the BIOS IC, and on 34, we can find the BIOS programming pins. With these pins, you can flash the BIOS in circuit without removing the BIOS. In area 35, you can find these two pins, and when you short this pin to ground, it will trigger an intruder signal. The intruder signal, sometimes referred to as the intruder detection signal, is used in modern computer motherboards as a part of a security feature to detect physical...

desktop mboard refers to the precise order and timing in which power is delivered to the mboards different components during the startup modern desktop mboards house interconnected components like the CPU the random access memory and the chipset Each of

which depends on others to function correctly for instance the chipset or the PCH often needs to be powered before the CPU because it has to facilitate the communication during the initialization also the random access memory must be operational before the

CPU can access it for its first instructions a precise voltage sequence ensures that these dependencies are met allowing the system to boot successfully I don't know if the power sequence can be discussed in one video if not I will make a multi-part video at

the end of this course you will be equipped with enough knowledge to analyze and repair any moneyboard if you gained any value from this guide consider giv it a like and help me to grow the channel and create more content

that you enjoy and do not forget to subscribe to the channel for more in-depth analysis like this one so let's start in this video I will be analyzing the z270 gaming Pro from MSI which is a sth generation

mboard analyzing this 7eventh generation motherboard provides a basic understanding of motherboard architecture component layout and functionality that can be applied to higher generation motherboards understanding the power sequence of the Seventh Generation motherboard equips you with the framework to anticipate and

understand improvements in new generations of motherboards this knowledge will assist you in troubleshooting different motherboards and of course there will be little differences in the power sequence with each new generation motherboard and CPU manufacturer but the basic information

still applies the Intel z270 is a high-end chipset it was introduced in early 2017 it was designed to support sixth generation Sky Lake and sth generation kbl Lake Intel core processors the z270 chipset acts like a central Communication Hub it helps the different

parts of the computer like the CPU the memory storage and other devices to talk to each other think of the chipset as a traffic controller that directs data where it needs to go inside of the computer the chipset only works with CPU that the

chipset supports let's identify the most important components on this z270 mainboard this is the CPU and this chip here is the chipset z270 I have removed the rectangular heat SN that is above this chipset so normally it looks like

this on the other side this is the super iio chip this chip is responsible for managing Legacy and lows speed input output functions and that are not handled by the CPU or the chipset itself this is the feedb circuit also

known as the real time clock circuit this RTC circuit tracks time and date continuously even when the system is powered off it uses a small 3F battery to maintain its operation independently of the main power supply so when when

there is no Mains connected this battery will provide Power to generate a real-time clock signal this is the 24 pin ATX power connector this connector is the primary power supply connection that delivers electricity from the power supply to the

motherboard when you turn your motherboard on the power supply will generate different voltages that the motherboard needs this is the CPU power connector on one row it disconnect to ground and the other one will get the 12vt from the

power supply this power connector will deliver the necessary power to the CPU these connectors typically come in a form of four pins or 8 pins the power supply for the CPU is separate from the 24 pin ATX power connector because this power

connector is designed to handle High current and power demands that this CPU needs in this region there is a voltage regulator that will create 3.3 volts near the super iio there is a 3 three voltage regulator that will

provide power to the Super iio near the chipset there is a crystal located this Crystal will generate a clock signal of 32 khz on the end of the motherboard there is a voltage regulator that will generate 5 volt between these two pcie slots there

is a voltage regulator that will create threefold standby in area 12 there is a voltage regulator located that will generate one fold for the PCH chip or the chipset in Region 13 there are some voltages generated for the CPU and these

voltes are around one ft and is needed by the CPU PCC SD Powers the standby logic and parts of the CPU that must remain operational even in low power States like sleep or hibernation in Region 14 you can connect

the front panel connectors for the power button near AIO IC there is a USB controller this controller is responsible for generating the voltages and data signals from the different uh USB ports this voltage regulator will create the power for the USB at the rear side

so the power for the front side USB connectors is generated in this region in the region 18 19 20 and 22 these voltage Regulators will create the power for the DDR RAM memory the are different voltages that the DDR memory

needs and these Regulators will create that voltage in area 23 and 24 these are CPU voltages one is called vcci iio and the other one is called vccsa pcci iio refers to a voltage rail used to power the input and output

circuits that are in the CPU pccsa stands for voltage for system agent the system agent is a component inside the CPU that is responsible different task like managing the memory controller pcie lengths integrated graphics and other input output subsystems these two

voltage rail are also voltage rails for the CPU in Area 25 we can measure an important signal the PCH power okay PCH power okay is a signal generated by the PCH to inform the CPU and the BIOS that

this PCH has been properly powered and fully functional in area 26 you can find the CPU power good signal the CPU power good signal is generated by the VR Rams or the controller that powers the CPU it confirms that the CPU has received

stable power including the correct voltage and current and it is ready to operate without issues so the power generation for the CPU V cor is okay and the signal can be found here between these two sockets and also

on some dedicated pins on the ram slots there is a signal called dram reset when the system is powered on the dam reset active low signal is pulled low to reset Dam this ensures that the memory modules are in a nonn cleared

State before data is read or written in this area near the super iio there is a signal called platform reset active low the hash symbol in the case that it is an active low signal meaning the reset is triggered when the signal is pulled

low to ground so in every signal that has an hash it means that the signal is active low when it's pulled to ground in area 29 we can find the CPU reset active low signal when the CPU reset signal is pulled low it forces the

CPU into a reset State actively stopping its current operation and clearing any internal States or registers this ensures that the CPU starts executing from a known state once the reset is deasserted so the signal goes back high in area 30 we can find a CPU pwm

controller this controller will drive the vrms that will generate the V core for the CPU and the graphics core for the CPU in area 33 we can find the BIOS IC and on 34 we can find the BIOS

programming pins with these pins you can flashh the BIOS in circuit without removing the BIOS in area 35 you can find these two pins and when you short this pin to ground it will trigger a intruder signal the Intruder signal sometimes

referred to as the Intruder detection signal is used in modern computer mboards as a part of a security feature to detect physical tampering or unauthorized access to the system the signal is generated by a detection switch or sensor which monitors where

the computer case has been opened in this image I will explain what the most important components how they communicate with other components first the pcie 16 data Lanes so in this pcie slot you will connect the GPU and this communication will go

between the CPU and this slot these two slots have one data Lane and these two slots will communicate with the PCH this pcie slot has eight data Lanes and this communicates with the CPU this slot has four data lanes and

this slot will communicate with the PCH these two m.2 slots will communicate with the pch in area six are SATA ports and this SATA ports are communicating with the PCH on these two connectors you will connect the USB 3.1 ports and these

ports will communicate with the USB controller these two USB 2 o ports will communicate with the PCH the mouse and keyboard will communicate with the super IO chip the image output on this DVI connector comes from the CPU this USB 3.1 Port will communicate

with the pch in area 12 you can find the Len interface and the L interface will communicate with the L controller that is this chip in Area 13 you can find the front panel audio connector this connector communicates with the audio

chip you can connect a fan connector on this connector the pwm signal that will drive this fan will come from the super iio bwm signal that drives the CPU fan will also come from the super IO chip in area 16 this is the RGB LED

microcontroller so this will drive all the different RGB LEDs that are on on the board and this chip will get its data from the i c interface this the BIOS and the BIOS is a slave device and the master is the PCH

and this V core controller communicates with the CPU the debug LEDs are located here in area 19 and the debug state of these LEDs is driven by the PCH L controller itself also communicates with the PCH the audio chip also communicates with

PCH this USB controller that will drive the different USB ports also communicates with the PCH the PCH or the chipset communicates with the CPU the CPU itself communicates with the PCH it will communicate with a random access memory CPU will communicate with

the pcie slots of a data Lan and 16 data Lanes also the monitor signal that will go to your monitor comes from the CPU if the CPU supports integrated Graphics this signal will go to the DVI connector or the HDMI

connector the BIOS chip is located in this region when we zoom in then this is the BIOS chip the BIOS is responsible for the Post power on self test process where check checks the CPU the memory and other components to ensure that they

are working properly a malfunction or bug in the Bios can lead to a failed post causing the motherboard to appear faulty if the BIOS fails to initialize certain Hardware components like the CPU or Ram the system will not boot even if

the motherboard and other Hardware are functional and these problems are typically related to how the BIOS interacts with the hardware and software during the system startup and operation bios corruption is one of the most common reasons of mboard failures

the BIOS is stored in a nonvolatile memory usually a eom or flesh if the BIOS gets corrupted due to factors like power loss during a bios update interrupted updates or faulty software tools the system may fail to boot or the

motherboard may stop working entirely this could render the motherboard unresponsive as the motherboard cannot communicate with the CPU or other critical components without a working bios updating the bias improperly can result in a corrupted bias version causing the system to be unstable or not

boot at all this is why many motherboards include a dual bio system that offers a backup bias in case an update goes wrong newer Hardware components like a new CPU Ram module or GPU may not be compatible with old

versions of the BIOS if the BIOS does not support the latest Hardware properly the system may fail to recognize comp components result in poor performance or fail to boot altogether incorrect bio settings can lead to Hardware instability these settings may cause the

system to crash or fail to boot for example manually overclocking the CPU or Ram through the BIOS might result in an unstable configuration that can cause the system to fail if a user changes the settings like the CPU voltage memory

frequency or power settings the system might experience instability or even Hardware damage sometimes a simple set of the bias to default setting can solve this stability issues it's rare but the bio chip itself can also fail this can be due to

manufacturing defects overheating or power surges that damage the chip or its components when troubleshooting a motherboard it's essential to work in steps to identify the source of the problem I began by visually inspecting the motherboard for any signs of

physical damage this includes looking for burned comp opponents swollen or leaking capacitors or any visible damage to the PCB traces even a small crack or Scorch Mark could indicate a failure Point next I ensure that all connections were secure this includes the power

connectors from the PSU data cables for storage devices and other peripherals I also recce the RAM and CPU to ensure that they were properly installed as loose connection can often cause issues after confirming the physical Integrity of the components I and moved

on to testing I verified the power supplies output using a multimeter to ensure it was providing a stable voltage a failing PSU can cause erratic Behavior or complete failure to boot from there I tested each Ram stick individually in

different slots to rule out any memory issues I also double check the CPU for signs of band pins or improper seating as these are common sources of boot problems if no issues were found during this Tex The Next Step would be flashing

this bios this chip here is the PCH or the chipset and the SPI part is used to communicate with the BIOS chip so these are the pins that will communicate with the BIOS the PCH is configured as a

master device and the BIOS is configured as the slave device this pin here is a Serial clock pin this pin carries the clock signal generated by the PCH the output of this clock signal goes from the PCH to the BIOS chip the io2 pin is

used as a right protect pin and this signal is active low and prevents unauthorized writing to certain parts of the BIOS chip the signal goes to the input of the BIOS chip when the right protect signal is low the right

protection is enabled the io3 signal is configured as a hold pin the signal temporarily pauses the communication to the BIOS chip this is the mosy master out slave in pin and this pin carries data from the PCH to the bio chip the MOSI pin transfers

commands and data like read or write instructions to the BIOS chip the misop pin allows the BIOS chip to send the requested data back to the PCH so MOSI will send a command read or write instruction to the BIOS and the BIOS

will reply it on the Miso line when the chip select goes low it means the BIOS chip is selected to communicate with the PCH then the clock signal will start every bit transfer happens on a clock Edge either rising or falling depending

on the configuration so on every pulse a bit is sent and the same applies when the data is sent back to the PCH so every bit will be set on every clock pulse the chip select pin ensures that

only the selected bio chip is responding to the commands when the chip select is low the bio chip is active and data can be read or written this is the BIOS chip so this bios chip is in a slave configuration so

the PC is the master and the BIOS chip is the slave when the PCH wants to communicate with the BIOS chip it pulls the chip select pin low this is the chip select pin it comes from the PCH and it

will pull this line low next the PCH will generate a clock signal and this clock signal will go to this pin the clock pin after that the PCH will send a command a read or write command to the BIOS chip when the BIOS

chips want to send the information back it will send it on the myo pin back to the PCH the B ship needs power to operate it's 3.3 volts and when you look at the part number there's a little trick so if

there is no W after the F letter then you can conclude that this bi chip uses the 3.3 volt to operate when you want to flashh firmware to this B chip there are two options you can desolder this chip and Flash it on a

firmware flasher and you can also program it in circuit with these jumpers all the signal lines of these jumpers will go to the bio chip so then you can program it in circuit without removing this bio chip and this is how the bio circuit

looks like on a motherboard so these are the SPI jumpers and with these jumpers you can program your bios this is how the bias works when the power button is pressed on power up the PC8 send clock pulses via the serial

clock pin the PCH sets the chip select pin low to activate the BIOS chip the PCH sends read or write commands over the MOSI line to the BIOS the bio chip processes the commands and prepares the data for read

operations the BIOS chip sends the data back to the PCH via the Miso line for right operations data is sent from the PCH to the BIOS chip via the mosy line once the data transfer is complete the PCH sets the chip select pin High

deactivating the BIOS chip this is how an ATX power supply looks like an ATX power supply is a type of power supply unit designed to provide electrical power to the desktop computer that follows the ATX from Factor standard the ATX power supply converts

the high voltage alternating current from the wall outlet into a lower voltage direct current so it will convert the AC down to DC this DC voltage is needed by different components inside of the computer this connector will deliver the different

voltages to the motherboard the CPU connector is a 4 or8 pin connector and this connector will deliver 12 volt to the motherboard on the motherboard this 12vt will be converted into a VC core voltage for the CPU these are six or8 pin pcie connectors

and these connectors can be used to power the graphics card also storage devices fence cooling system and other peripherals when you connect this power supply to the wall outlet and you connect the 24 pin to the motherboard the motherboard will draw a standby

current the standby current should be between the 100 to 300 milliamp but it also depends on how many RGB LEDs are turned on in standby mode so if there are more LEDs it will draw more current you can measure the plus 5 Vol standby

with the multimeter put the black probe to ground and the red probe to the fivefold standby pin the plus fold standby rail in the ATX power supply provides a small amount of power to the motherboard and also to certain

components so even when the computer is turned off or it is in a low State like sleep or hibernation it will draw a small amount of power the standby power is needed for enabling specific functions that are required to remain

partially powered even when the main components are off if you want to see if the power supply generates all the voltage there is a test that you can do what you can do is you can connect the PS on pin to

ground with a paper clip or wire to check if the power supply turns on and works properly without being connected to the motherboard so when you jump the PS on to ground it will generate all those voltages PS on pin is used to

control where the power supply is on or off this pin is located on the 24 pin ATX connector and by default this pin is 5 volt High when you jump this pin to ground this power supply will be turned on and

it will start generating all these voltages the resistance on this PS1 pin is very high this is the 24 pin power connector on pin 9 you can find the standby voltage of 5 volt the standby voltage of 5 volt is

used on the motherboard for different components like the super iio chip uh most of the time this 5vt is converted back to 3vt standby voltage uh so there are different components on a motorboard like a USB highight switch some

controllers USBC controllers uh some low Drop voltage Regulators all those chips needs power in standby mode when the power supply is turned on on pin 14 there will be minus 12 volt created this voltage of minus 12 volt is used by the audio

amplifier from the 5vt standby voltage the standby voltage of three volt will be created the standby voltage of three volt is needed to power the super iio chip and to generate signals like the power button signal if the power button

signal is missing the main board will not power on and that is because the 3.3 volt is needed to generate a pulse that will go to the super iio chip also the 3F standby will be converted into threefold

siio the three-fold siio volage rail on the motherboard stands for a 3F South Bridge input output this rail supplies 3.3 volt to the super iio chip this is the power sequence flow diagram for a 7 generation Intel motherboard the motherboard power

sequence is a series of steps that ensures that the computer powers on safely and initializes all components correctly in short the power sequence in a motherboard begins with power detection when the power supply is connected and turned on uh the

motherboard detects a stable power source and activates standby power when you press the power button it will eventually send a signal to the power supply to start delivering full power to all voltage rails once the power supply stabilizes and

verifies the voltage levels it send a power good signal to the motherboard this ensures that the power is safe for the system to operate the motherboard then uses its voltage Regulators to adjust the incoming power to correct levels needed for different components

such as the CPU memory and the chipset next the mboard initializes it clock signal which creates the timing signals required to keep all components working in sync after this a reset signal is sent to ensure every part of the system

starts from a stable known State the mboard firmware bios then takes over it performs a series of checks called the power on self test to ensure that the critical components like the CPU RAM and storage are functioning correctly after the components pass

these checks they are powered up and initialized one by one in specific order process ensures that each part of the system receives the power SA safely so the computer can transition to loading the operating system so what you see here is the power

sequence of this Intel board every voltage or signal has to be created in the right order so let's say if the sio3 fults is missing it will not proceed to The Next Step this is the sequence for the RTC

circuit and after that we have a standby sequence followed by a power on sequence when the motherboard is turned on eventually these two reset signal has to be released when these two signal are released then you have a initialized

motherboard the power sequence is for every motherboard and every different chipset a little bit different the most important part is to measure the signal that are important for booting the motherboard like the PCH power okay the reset signals power good signals the

Sleep modes the ATX power okay CPU power good bch power good the most important signal that are on every mboard is the platform reset signal and CPU reset signal these two signals eventually have to go to a high

State the mots have different states the G3 State also known as a mechanical off State the system is is physically unpluged from the main power source only the RTC battery is connected so the RTC battery will provide power to the RTC

circuit then we have the S5 state every voltage rail or signal at this point has some kind of state in the S5 State the system is shut down with no active memory or task but with standby power maintained for specific wake up events

one of those events is the power button so when you press the power button you want that the motherboard goes into power on State and this is the power on state the working state so the system is fully powered on and operational all

components are actively running in this state you know which voltages has to be present and what the signal should be I will give an in-depth analysis for each sequence I will start with the first one and I will work it down to the

last two signals that are the reset signals I have analyzed 37 steps so let's start in the first Power sequence we have to create the RTC power for the PCH the ATX power supply is not connected to the power outlet so we are

in G3 State and G3 state is the mechanical off State so it is physically only the motherboard with the RTC battery on it in that case we have to generate the power for the RTC circuit that comes from the coin cell the

battery and we have to also create a reset signal that is high the creation of the RTC power is done in this region this circuit is part of the RTC circuit this circuit delivers the RTC power to the chipset or

PCH when the ATX power supply is not connected to the power outlet then this power the Feb power comes from this RTC battery the RTC battery is a coin cell battery of 3 volts that provides the power to the PCH oscillator circuit even

when the computer is turned off or unplugged when you have your motorboard in your hand and the A6 power supply is not connected the power for the RTC circuit has to be generated and this comes from the coin cell

battery when the adx power supply is connected to the power outlet then there will be a standby voltage created and this standby voltage will be converted into 3.3 volts and the 3.3 volt will be the source for the

feat the main function of the RTC battery is to keep the clock running and press serve bio settings when the computer is powered off without the RC battery when you power up the system after it has been unplugged the system

might show incorrect time and reset certain settings as it loses the data stored in the RTC chip when the system is powered down the RTC battery keeps the PCH oscillator circuit powered on so the time and system settings are

preserved there are two power sources that provide the power to the RTC circuit the first one is feet that is powered from a coin cell battery and the other source comes from a 3.3 voltage regulator this provides power when the

system is on when the system is shut down or the ATX power supply is disconnected the power comes from the battery this component here is a short key diode array this diode array can be used in power switching to ensure that

the real-time clock receives the correct voltage from either the RTC battery or from the standby 3.3 volt voltage regulator this short key diode array has a low voltage drop and it is used for fast switching between those two

sources the configuration of this diode array is also known as a common cathode configuration the common cathode configuration means that the cathode of these two shortkey diodes are shared one anode is connected to the battery and the other one is connected to the 3.3

standby voltage diode connected to this regulator will be forward biased because because the anode is connected to the output of the regulator and this voltage is higher than the cathode voltage of the feed the current will flow from the

regulator through the diode to the feet power line the feat diode will be reverse biased because the feat is at a lower voltage so no current can flow from the battery to the feat voltage rail when the system is powered down and

the regulator no longer provides power the voltage at the regulator side the anode side drops to zero the diode connected to the feat will now become forward bias because the battery voltage is higher than the voltage at the code side the current will now flow

from the battery through the diode to the fat voltage Rail and that will power the PCH oscillator in the PCH uh chipset this voltage rail will go from low to high and it will power the PCH oscillator circuit this diode array has

a low voltage drop of 0.2 or 0.3 volts which ensures that the voltage reaching the RTC is as close to the source voltage as possible the shortkey diod array can quickly switch between those two sources ensuring a seamless

transition between the battery or the regulator without interrupting the rtc's operation because this voltage is very stable on most motherboards this resistor between the coin battery and this diode array is 1 KMS in power sequence one we need to

create an RTC power of 3 volts in standby mode and Power on mode this voltage has to be present so it has to be around three F High and the signal is created on the motherboard and will go

to the PCH S5 is a standby mode so the ATX power supply is connected and the 5f standby voltage is created and s0 is power on so when you press the power button the system boots up and that is

the s0 state on every motherboard you can find a Coin cell battery and near this coin cell battery battery there is some RTC circuit that will generate the power for the RTC oscillator circuit and the oscillator circuit is implemented in the

PCH now we can identify the shy diode array that is here so this diode can switch between the battery voltage or the 3.3 standby voltage that is created by the ATX power supply in this case we have disconnected the power supply from

the power outlet so the power can only be generated from the battery in that case the battery voltage will go through this short diode array at the output this voltage will go to the feat PCH voltage rail that will go to the PCH

when we look at the first power on sequence power for the RTC circuit we are in the G3 State and the signal has to be high cuz this is low this is high and the reset signal also has to go from

low to high so when you have your MBO in your hand these two signals should be high because of the coin cell battery because of this battery and this resistor here is the one kiloohm resistor next we have to change the

state of different reset signals to go out of a reset State we have to put the signal from low to high the hash behind the signal name indicates it's active low and because it's active low it's still in a reset State and the signals

has to go in an active state so from low to high also in power sequence one we have to create different reset signals and these reset signals are created from the the fbat PCH voltage rail if you remember this feat PCH was created from

a coin cell battery or the 3.3 standby voltage when this voltage is present the secondary RTC reset signal will go high then we have the primary RTC reset signal will also go high and the Intruder signal will also go from low to

high on most motherboards the resistor that is used to create the reset signal is around 20 kiloohms also be aware if the this capacitor is shorted to ground this signal is missing so it's in a reset state if you see this reset signal

is low check all the capacitors maybe one of those capacitors is shorted to ground but Intruder signal most of the time this resistor is 1 MGA ohm the Intruder signal with the hash symbol indicates a active low signal and it's

typically used for a temper detection signal the purpose of the signal is to alert the system when there has been an unauthorized attempt to access the internal component such as opening the case or removing a cover so that will

trigger this signal the most common response is that the system will display a warning or alert message on the screen indicating that a intruder signal has been detected the realtime clock reset signal is a control signal used to reset

the RTC on a system the RTC is responsible for maintaining the system's time and date and even when the system is powered off what will happen when the realtime clock reach reset signal is triggered when the real-time clock reset

signal is active low it resets the RTC which result in the loss of time and date settings this is the same as removing the power from the RTC causing it to revert to its default State usually by resetting the date and time

to a default date of time this is called a secondary real-time clock reset signal it's the same as this reset signal the secondary RTC reset signal can trigger some uh addition functionality within the PCH the secondary reset signal is basically the

same as the primary RTC reset signal in power sequence one the voltages Ford signals will go from low to high in the standby state or power on state the voltage of these signals has to be high these signals are created from the main

board and it will go to the PCH the RTC power will eventually go to the PCH on the standby stand State and the power on State this voltage rail has to be high the PCH receives the RTC power and it will go to the oscillator

circuit that will drive the crystal of 32.768 khz and will also provide power to the internal Ram or bios where the settings are saved on the left we have the platform controller Hub the PCH or chipset at these capacitors and resistors you can

measure the signals be aware that these signals will be on different location depending on the motherboard and manufacturer but most of the time these capacitors and resistors are located near the PCH chip in power signals 2 we have to

create a RTC frequency and the frequency is 32.768 khz so this frequency has to be generated the RTC power the PCH oscillator circuit and the RTC Crystal completes the RTC circuit the RTC crystal is responsible for providing the

oscillation or clock signal to the RTC chip so in this case the PCH chip this Crystal generates a very precise frequency usually 32.768 khz which the RTC circuit uses to keep track of time this frequency is divided down by this RTC chip that is

located within the PCH chip to maintain the seconds minutes hours and days when a motherboard is powered down the RTC power keeps this RTC chip powered in this PCA chip so the time and system settings are preserved so the

frequency of 32.768 khz has to be always present at this Crystal with an oscilloscope you can measure the frequency at 0.1 or two on one side the waveform is smaller than the other one in power sequence two we have to

generate a RC frequency of this frequency has to be generated all the time in the PCH there is a pin called PCH suspend clock pin the suspend clock pin inside the PCH converts the incoming 32.768 khz sinus wave clock signal into

a square wave the square wave is used for the timing and synchronization so it will convert the sinus wave that we see here so this is a sinus wave it will convert this waveform into a square wave the actual conversion

from sinus wave to the square waves happens in the PCH chip when you look at the motherboard near the PCH chip there will be a crystal at the output one or two you can measure the waveform with an

oscillator sometimes it's also possible to measure the square wave these components will be located near the PCA chip in power sequence 1 and two the ATX power supply was not connected Ed to the motherboard in the power sequence 3 the

ATX power supply is connected to the motherboard and also to the power outlet in that case the standby voltage of 5 volt has to be generated by the ATX power supply the first two sequences we measured the frequency based on the

mechanical off State now we have connected the ATX power supply to the motherboard and also to the power outlet the next power sequences are all related by the standby power sequence sequence so we have to look at all the signals at the standby

State for the RTC circuit and the standby sequence every signal at a standby state has to be correct for the RTC battery it has to go high for the reset signal has to be high the ATX power supply should

generate 5vt standby voltage so this 5 volt has to be present then we need 3.3 volt so the state of every signal or voltage has to be present at this location and if you measure these voltages on the motherboard or the

signal lines and these signals or voltages are not correct based on this line then you know you have a problem because your system will not boot according to the power sequence 3 we need 5 volt standby voltage from the ATX

power supply 24 pin connector is located here this is the ATX power supply it is connected to the motherboard and also to the power outlet on pin 9 the 8X power supply should generate 5vt standby voltage and this 5 volt has to go from

low to high and high is 5vt and this voltage will be used by different voltage Regulators to create standby voltages for the motherboard so basically after the RTC clock circuit is running and the frequency of 32 khz is

created in the third sequence we have to generate the standby voltage of 5 volt and that has to be present on the mboard you can find the 24 pin power connector and on pin 9 the standby Vols of 5 Vol

should be present and the resistance value is higher than 700 ohms so in the standby State and Power on State this voltage should be present and it comes from the ATX power supply when the standby voltage of 5

volt is created we can move to the next power on sequence that is number four in step four we need to generate 3.3 volt in the standby State 3.3 volt has to be present this is the voltage regulator

that will create the 3.3 fold the 3.3 volt will be used for the RC power circuit so this 3.3 volt will go to the PCH from the 5vt standby voltage the 3.3 volt is created this is an ldo it will

convert 5 volt to 3.3 volt from the 24 pin ATX connector on pin 9 it will go into this voltage regulator it will start regulating because the enable signal deres from the 5vt standby voltage it will turn this regulator on

we have input voltage of 5 volt and then it will generate 3.3 volt this voltage rail is called threefolds Duell standby well and the resistance value on the output is 20 KMS The threefold Duel standby well is a power rail that

provides a 3.3 volt Supply to certain components even when the system is in a low power state or standby mode this voltage rail ensures that specific circuits such as those necessary for the wake up land real time clock or other

components that remain powered on when the rest of the system is turned off voltage for these signal lines comes from the 3.3 volt so this voltage rail will deliver power to the component that needs to be always turned on in a

standby State this voltage rail will go from low 0 volts to 3.3 volts and when it's powered on It's Still Remains 3.3 volt this voltage is created on the main board this is the voltage regulator it will convert 5 volt standby to 3.3 volts

so this voltage ra will go from low to high this voltage ra will go to the RTC power circuit this is diode array we now have a 3.3 volt at input one that comes from the voltage regulator the voltage

compared to the battery power is higher so this diode array will pass the source voltage of 3.3 volt to the PCH and the connection from the battery will be disconnected when you want to reset the bios you can remove this battery or jump

this jumper when the 3.3 volt dual standby well is created the next power sequence will create 3.3 volts that will power the super iio chip when the motorboard is turned on this voltage rail remains high this voltage regulator will create

3.3 volts and it will power the super iio chip the voltage rail that this regulator creates is called super iio 3F auxiliary this voltage regulator will convert 5 volt that comes from the standby power rail from the ATX power

supply it will convert it to 3.3 volt this voltage rail is a secondary power source used when the main power supply is unavailable or off because when the mboard is powered on the super iio chip gets its power from the 3.3 volt power

on rail instead of this rail and that's why the letter a is in this voltage rail a stands for auxiliary voltage or secondary Supply to enable this voltage regulator there is a signal called RTC reset this has to be high because it's

not in a reset State when the signal is high it will create an unable voltage that will turn this voltage regulator on the resistance of this 3.3 voltage is higher than 3 kiloohms for power sequence 5 the voltage 3.3 volt has to be created in

standby state it will go from 0 FTS to 3.3 FTS and in the power on state it remains 3.3 fold and this voltage is created on the main board if this voltage is not present the motherboard will not respond to any event or

signals this is a super IO chip this is the voltage regulator it will convert the 5 volt standby voltage to 3.3 FS that will power this super iio chip this is the RC reset line this has to be high

because we are out of a reset state so there will be a voltage present it will generate an enable signal this voltage regulator will turn on it will create 3.3 Volts for the super iio chip and this voltage goes to pin 46 and pin

85 when a super iio is powered on the next sequence will be to generate a de power okay signal that will go from the superio chip to the PC chip in the standby State the signal will go from

low to high and in the power on state it remains high pchd power okay signal comes from the siio chip and it will travel to the PCH chip but the signal will be created in the siio Chip And it indicates that

all the power it needs is stabilized and okay to use it will send a signal to inform the PCH that it's working fine this is a super iio chip on this in the super iio D power okay is generated

it will go from low to high the power supply for the super iio chip will also generate this signal line D power okay typically stands for deep power okay or deep power well okay the signal is generated by this super iio chip it's a

signal output from the super I chip that indicates a specific power rail has stabilized and it's operational in power sequence 6 there has to be a voltage created of 3 volts in a standby state it goes from low to

high and in the power on state it remains High and the signal travels from the super IO chip to the PCH chip so this is the super iio chip and near this chip you have some resistors at this resistor you can measure the

super iio D power okay signal and also the D power okay signal that comes from the SI so this signal will go through this resistor from here it will go to the PCH and the signal will go from low

high this is the PCH and the sio D power okay signal that comes from the siio will go into this PCH when the SI de power okay signal is present then you can assume that the RTC circuit is

working on this motherboard you can measure the s d power okay signal near this diode on the other motherboards you have to check the schematics where the signal is present the next two sequence sequence number seven and eight are called Sleep

suspend and super iio sleep suspend in the standby State the First Signal has to go from low to high and the super iio sleep suspense signal will go from high to low in the power on state the Sleep

suspense signal will remain high and the sio Sleep suspend will remain low basically the super iio sleep suspend is an inverted signal of the Sleep suspense signal this signal comes from the PCH and it goes to the super

iio chip and this signal the siio Sleep suspend is generated by the super iio the two signals can be measured near this super iio chip the first sleep suspense signal will come from the PCH it will go through a resistor and into

this super iio chip so the two signals can be measured near this super iio chip this is the PCH chip it will output the Sleep suspend signal the SLP stands for sleep and the SS stands for suspend so

the Sleep suspend is a power management signal used to indicate that the system is entering a low power State such as state S3 that is sleep S4 is hibernate and S5 is soft off the PCH or the sio

chip can trigger an reset signal by pulling this signal too low the Sleep suspend signal is a very important signal that comes from the PCH because it can trigger a reset signal this is super iio chip this is

the resistor and on one side the signal sleeps Su spend comes from the PCH and it will go into this super iio chip this signal has to be around 3 volts in standby state it will go from low to

high and in a power on state it remains High and the signal comes from the PCH chip and it will go to this s chip in power sequence 8 is the same signal but it's inverted so this is the

PC signal the Sleep suspend this was high and with this circuit it will be converted to low and this signal will go into this super iio chip the signal line super iio sleep suspend is derived from the 5V standby

voltage the signal line can be found at a resistor near the siio ship the resistance of the signal line is higher than 9 kohms and if you look at this resistor the 5vt will be the power supply to

generate this signal and that's the resistor here superio sleep suspend signal in a good workking standby mode it should be Zer volt so in the standby state it goes from high to low and in the power on state it remains low and

the signal comes from the siio this signal will create different enable signals for creating the 3.3 volt standby plus 5 volt and it will also create the enable signal for the PCH core voltage if the signal is missing

the moo will also not respond to any signals or events this is a low Dropout voltage regulator it will create a standby voltage of 3.3 volt this 3.3 volt is Created from the 5V standby that comes from the ATX power

supply and it can also be created when the ATX power supply is turned on it will create a FCC 3.3 volt and this voltage can be the source for this voltage but the important one is the signal super iio sleep suspend it goes

on high to low because it's a low signal this mosfet is turned off and there will be a 3.3 volt enable signal present on the enable pin the voltage regulator will turn on and it will generate a 3.3

volt based on the 5vt standby or the VCC 3.3 volt in a power on state the important one is that the sio Sleep suspend signal is the signal that will enable this voltage regulator to create 3.3 volt we need an enable signal to turn this

regulator on and then we have the 3.3 standby voltage this voltage regulator will create a 3.3 standby voltage and the super iio sleep suspense signal can be measured here also the super iio sleep suspend signal is used to set the mode for the

5f dual power rail this is a super iio sleep suspend signal it goes from high to low it will set the mode for this voltage regulator and this voltage regulator will generate 5 volt it's called 5vt dual because this

voltage has to be present on the power on state or in standby mode so this voltage has to be present all the time and the source for this power ra can be derived from the 5vt standby voltage or

when the ATX is powered on it will get its 5 volt from the 5 VCC pin based on this enable signal and also the sleep mode S3 3 and S4 it will determine what the destination voltage will be so 5f

dual can come from the 5f VCC or from the 5V standby voltage depending on the mode and those two sleep States basically the super iio sleep suspense signal is responsible for determining the destination voltage for this 5f dual so it comes from the 5V PCC

or the 5vt standby voltage from the 8 six power supply in standby mode the super iio sleep suspend signal is used to determine which source power rail will be used to generate the 5vt dual power rail also the super iio sleep suspense

signal is used to enable the PCH core voltage so this will create an enable signal called the PCH onefold standby enable and this enable signal will go to a voltage regulator that will create the one ft that is used for the PC H

chip with this transistor the enable signal is created for the 1vt bch core voltage to summarize the super iio sleep suspense signal is a important signal to measure because this signal will be used to generate different enable signals

that will create different voltages if the signal is missing the mon will not respond to any events and it will also not boot when the superio Sleep suspend signal goes low it will generate different voltages so the next power sequence will

be to create the 5vt Dual 5f dual is a 5vt power rail that is always generated so the source voltage can come from the ATX power supply from the 5vt standby pin and when the 8X power supply is

turned on it can get its 5vt from the 5vt VCC pin in the standby State this voltage goes from 0 volt to 5 volt in region 10 here is where the 5vt Dual regulator is located so this will create

the plus 5 Vol power sequence 9 we have to create a plus 5 volt and the source voltage can come from the plus 5 volt standby voltage or the 5vt VCC when the 8X power supply is turned on in combination with

the mode pin and the state three and state 5 bin it determines where the source voltage comes from so in this case the sio sleeps a pend pin is low so this S5 mode will be high so apparently the Sleep S4 signal

will be low because of this state The Source voltage will be 5 volt standby and this comes from the 5 volt standby voltage from the ATX when the Sleep S3 State and the Sleep S4 state is high it

will get its source voltage from the five volt VCC and that will be generated when the power supply is turned on the output of this 5vt dual power rail is higher than 9 kiloohms this is the voltage regulator that determines where

the source voltage comes from but eventually at the output we have to have plus 5 volt the super iio sleep suspense signal has created 5vt Duell voltage Rail and now the super iio sleep suspense signal will create the 3vt standby voltage so

this three volt standby voltage will be a voltage of 3.3 volt this is a standby state and the 5f Dual is now high so this is 5 Vol and next the 3.3 volt has to go high so it

has to be 3.3 volt in the standby State and when it's fully powered on these voltages are still present between these two pcie slots the voltage regulator is located that will create the standby voltage of plus 3.3 volts in power sequence 10 we have to

create the 3.3 standby voltage this voltage comes from two sources one is from the 5f dual power ra that we created in the previous sequence and when the aex power supply is turned on it will get its 3.3 Vol

from the VCC 3 pin the sio Sleep suspend signal that you create in the previous power sequence is low and because it's low this mosfet is turned off and then the enable signal will be present at this location and it will be the input

for this voltage regulator when the enable voltage is present it will turn this voltage regulator on and it will create the three F standby voltage if this voltage is missing what you can do is you can jump the pin PS on

from the ax power supply to ground it will force the ax power supply to generate the power on voltages then this 3.3 volt will be available and the 3.3 volt standby voltage will be present and if the motherboard is working after that

then you can conclude that standby voltage of the 5f Dual is in or something in this circuit in standby mode this voltage goes from low to high to the 3.3 volt and in the power on state it's still high at 3.3

volt this is the voltage regulator chip that will create a 3.3 standby voltage the resistance on the output is higher than 500 ohms this chip is located between those two PCI slots when the standby voltage of 3.3 volt is present it is used to enable the

PCH core voltage because the 3.3 standby voltage is present here it will short this voltage rail so the gate has no voltage because of that the enable signal that will create the core voltage for the PCH will be high when the stand

voltage of 3.3 volt is missing this enable signal will be shorted to ground on these two transistors we can find the PCH onefold enable signal when the standby Fage of 3.3 volt is created the next sequence is to create

the 1.8 volt I could not find this voltage rail on the motherboard so I will skip this one but the next power sequence is number 11 and in this power sequence we're going to create the onefold core voltage for the PCH chip so

in the standby State this PCH voltage has to go from 0er volts to 1 volt this is PC chip and near this chip there's a voltage regulator that it will create the core voltage of 1 volt that will be

used by the PCH the voltage regulator is located in region 12 so in power sequence 11 you're going to create the one fold that will be used by the PCA chip this is a bug boost converter and this converter will use

the 5 F to generate the onefold the PCH 1 F en comes into pin 7 and it will turn this chip on and this NAA voltage is derived from the 3.3 standby voltage as you can see here standby voltage of 3.3

volt is used to create this enable signal and this enable signal will turn on this bug boost converter to generate the 1vt PCH core voltage the output resistance is higher than 30 ohms but to summarize we have to create one fold in

standby state it will go from Z FTS to one F and in the power on state it remains High the signal is created on the main board board and will go to the PCH power supply for this chip comes

from the 5vt so this 5vt can be this 5vt standby voltage and from the ATX power supply when the power supply is turned on so this is the pwm controller also known as the bug boost converter it will

drive the high side and the low side mosfet and at the output you can find the onefold for the PCH chip when the PCH chip is up and running the next power sequence is the VCC STD PLL this

is a CPU voltage and in the standby state it remains low so there has to be zero volt at the voltage rail that will go to the CPU also the power good signal from the VCC STD power regulator remains

low basically this voltage rail that will go to the CPU and the power good signal will go high once the system is powered up but in this case we're still in the standby state it remains low this is CPU and near the CPU there is a

voltage regulator that will create the VCC SD voltage rail that will go to the CPU also the power good signal will go to the CPU this is the voltage regulator that will create the one volt for the CPU the power supply for this voltage

regulator comes from the 5vt Dual voltage Rail and that drives from the 5vt standby voltage from the ATX power supply or the 5 VCC pin from the power supply when it's turned on when you turn on your motherboard these signal the

Sleep State 4 and sleep state three will go high that will create this enable signal then the voltage regulator will start generating the one fold for the VCC SD and that will go to the CPU the output resistance of the VCC SD voltage

rail is higher than 200 ohms the VCC SD voltage is Created from the 3.3 standby voltage the VCC SD is a power ra that serves the standby logic and certain supporting circuits within the CPU it also Powers the PLL section of the CPU

and PLL is also known as a face locked Loop a PLL is a component in the CPU that generates high frequency clock signals used to synchronizing operations across the processor cores and other components this is CPU this is the

voltage regulator the input voltage is 3.3 standby voltage and eventually depending on the Sleep States 4 and three it will turn on or off this enable signal when this enable signal is present it will generate the VCC St CPU

voltage of 1 volt and that will go to the CPU the VCC ST power good is a power good signal that is used in the CPU to indicate the Readiness and stability of this VCC STD power rail the resistance on this line is

higher than 2 kiloohms the VCC ST power good signal is 1 volt in the standby mod this signal is not present and when you power on your motherboard the signal will go from 0 Vols to 1 1 volts the signal is created

on the main board and it will go to the CPU near this voltage regulator this power good signal will be created the VCC SD power good of one volt and that will go to the CPU the reset M signal is the last

signal that is needed in this standby sequence a high reset M signal means that the system is stable and no reset or resume operations are currently happening so basically the system is waiting for event to trigger a transition from the standby state to an

active or awake state so it is waiting for an event like the power button or the reset button that has to be pressed so for now this process is finished and when this signal is high so this is the

last signal then you can assume that all the previous voltage rails are okay and now it's just waiting for an event The recet Mask signal can be found at the super iio chip at Pin 101 and the signal will go to the

pch in the standby sequence number 14 this reset Mass signal has to go from 0 volts to 3 volts and the signal can be found at the Super O chip at Pin 101 so there's a pin called reset Master active

low this signal is an active low signal indicated by the Hesh suffix and the signal is generated by the super IO chip the primary Ary purpose of this reset M signal is to perform a system reset during different Power

States basically in standby sequence 14 the signal has to go from 0 volts to 3 volts so in the standby state it goes from 0 volts to 3 volts and in the power on state it remains High and the signal

comes from the super iio chip and it will go to the PCH this is a superio chip at Pin 101 you can find the reset Master signal so it has to go from 0 volts to 3 volts this reset M signal comes from the super

iio chip and it will go to the PCH the voltage for this reset M signal is Created from the 3vt standby voltage these resistors are called pullup resistors so the voltage for the reset M signal is created here and it is about

3.3 volts when the system wants to reset it will pull this line low it will create a pulse and this pulse will go to the PCH and the PCH will start a reset process if you can identify the PCH you

see a lot of resistors near this PCH and one of those resistors is where you can find the reset Master signal when you want to troubleshoot a motherboard you can measure all those power rails and signals but most of the

time you can just jump to the most important signals like the resume Mass signal if the signal is high You can conclude that all the previous voltage rails are present because if there is a voltage rail missing the signal will not

be generated let's say for example that the 5 ft is missing then the FES that are created till the 5 volt are present and after the five volt power ra all those voltages are not present then you can

conclude that there is something wrong with the 5vt power ra and then you can focus on this power wheel so there can be a short present at this voltage regulator maybe an un enable signal is missing maybe some components are

damaged but this is how you can troubleshoot any motherboards just go to all the power sequences and check if these voltages are present so basically this is it these are the most important standby power on sequences and the

system is now waiting for an event and that event is pressing the power button and that will be discussed in the next video about the power on sequences in this video I have explained how the standby fages on the motherboard

must be created in the correct sequence to get a stable standby state in the standby State the motherboard is waiting for an event to trigger the power on sequence so basically the motherboard is now waiting for an event to continue the

power on sequence this event which the motherboard is waiting on is pressing the power button when you press the power button it will create a pulse and this pulse is the start of the power on sequence in the next video I will

explain what will happen when you press the power button which voltages and signals needs to be created in which sequence if you gained any value from this video consider giving it a like it will help me to grow the channel and

create more content that you enjoy and do not forget to subscribe to the channel for more in-depth analysis like this one so till next time bye-bye