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Hardware CategoryCritical Fault41 Step-by-Step Resolution Guides

Won't boot

Black screen, no POST, stuck on logo

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Showing 41 of 41 researched guides in this category.

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Critical5 steps

PC completely dead (no lights, no fan spin)

The system receives zero electrical power when pressing the power switch, leaving all LEDs dark and fans motionless.

No response when pressing the power button
Motherboard standby LEDs do not illuminate
Open Step-by-Step Fix
Critical5 steps

Fans spin for a second then immediately shut off

The power supply initiates boot but triggers internal short-circuit protection (SCP/OCP) almost instantly to prevent component damage.

Fans spin for half a second before halting
Power LED flashes once then turns off
Open Step-by-Step Fix
Critical5 steps

Motherboard powers on but hangs on CPU debug LED

Motherboard LEDs and fans operate, but the Power-On Self-Test fails at processor initialization, leaving a solid red or white CPU diagnostic LED.

EZ Debug CPU LED stays illuminated continuously
Monitor stays in sleep mode with no video signal
Open Step-by-Step Fix
Critical5 steps

Motherboard hangs on DRAM debug LED (no display)

System fails POST during initial memory training, indicated by a yellow or amber DRAM indicator LED and no screen output.

DRAM diagnostic LED stays solid amber or yellow
No video output to monitor
Open Step-by-Step Fix
Critical5 steps

VGA debug LED lit or 1 long, 3 short beeps

The system passes CPU and memory checks but cannot initialize video output or detect a display adapter.

VGA debug LED remains lit white or red
Speaker emits 1 long beep followed by 3 short beeps
Open Step-by-Step Fix
Critical5 steps

System boots to BIOS or hangs on BOOT debug LED

Core hardware initializes successfully, but the motherboard firmware cannot locate an active operating system boot loader.

Motherboard BOOT LED stays green/yellow
PC boots straight into BIOS setup screen on every power up
Open Step-by-Step Fix
Critical4 steps

PC freezes on motherboard splash screen (spinning dots freeze)

The system completes POST and displays the manufacturer logo, but halts indefinitely during early hardware enumeration.

Stuck on ASUS, MSI, Gigabyte, or ASRock logo
Windows spinning loading circle freezes solid
Open Step-by-Step Fix
Critical4 steps

Display goes black after Windows loading dots

System finishes UEFI/BIOS handover and starts loading Windows, but cuts video signal the moment the display driver initializes.

Windows logo appears then monitor goes completely black
Monitor goes into standby or displays 'Out of Range'
Open Step-by-Step Fix
Critical5 steps

BSOD with INACCESSIBLE_BOOT_DEVICE at startup

Windows kernel loses access to the system partition during early startup due to changed storage controller modes or missing AHCI/NVMe drivers.

Blue screen with stop code INACCESSIBLE_BOOT_DEVICE
Immediate reboot after splash screen into automatic repair
Open Step-by-Step Fix
Critical4 steps

BOOTMGR is missing (Press Ctrl+Alt+Del to restart)

Legacy BIOS system cannot find the Windows Boot Manager file in the active partition volume boot record.

Black screen with white text: 'BOOTMGR is missing'
Pressing Ctrl+Alt+Del loops back to identical error
Open Step-by-Step Fix
Critical4 steps

Stuck in 'Preparing Automatic Repair' loop

Windows repeatedly crashes during boot, triggering diagnostic repair which fails and restarts the loop.

Screen displays 'Preparing Automatic Repair' followed by 'Diagnosing your PC'
Error: 'Automatic Repair couldn't repair your PC' with SrtTrail.txt log
Open Step-by-Step Fix
Critical5 steps

PC power cycles infinitely every few seconds

System powers on, spins fans for 3 to 10 seconds, shuts down, and automatically turns back on in an endless loop before video output.

Endless loop of turning on and off automatically
No display or BIOS splash screen ever appears
Open Step-by-Step Fix
Common5 steps

CMOS Checksum Error (resets settings on every boot)

Motherboard non-volatile memory loses stored configuration and date/time whenever AC wall power is removed.

Prompt: 'CMOS checksum error - Defaults loaded' on boot
System clock resets to year 2018 or 2020 every shutdown
Open Step-by-Step Fix
Common4 steps

Stuck on BitLocker recovery key entry screen

Windows stops boot and requests the 48-digit BitLocker recovery key because hardware integrity or TPM state changed.

Blue screen titled 'BitLocker' requesting 48-digit numerical key
Key ID displayed with message: 'Enter the recovery key for this drive'
Open Step-by-Step Fix
Critical5 steps

Black screen and no POST following a BIOS update

A failed, interrupted, or corrupt BIOS firmware flash leaves the motherboard unable to execute Power-On Self-Test.

PC powers on but displays nothing after a BIOS flash
Fans run continuously with no keyboard or mouse LED activity
Open Step-by-Step Fix
Common4 steps

Front panel power button broken or disconnected

The chassis momentary power switch is broken, internally shorted, or disconnected from the motherboard front panel pin block.

Pressing power button feels spongy or doesn't click
PC turns on when using motherboard onboard start button but not case button
Open Step-by-Step Fix
Common5 steps

CMOS battery dead (BIOS clock and settings reset on every boot)

The CR2032 motherboard coin cell battery is depleted, causing the BIOS to lose time, date, and custom memory XMP/EXPO settings whenever mains AC power is switched off.

Windows clock shows 00:00 or incorrect year after turning PC on
Motherboard prompts with 'CMOS Date/Time Not Set' or 'Press F1 to Run Setup'
Open Step-by-Step Fix
Critical4 steps

Secure Boot Violation: Invalid signature detected

The UEFI firmware blocks the operating system bootloader because its digital signature has expired, been revoked in the Secure Boot DBX database, or belongs to an unauthenticated secondary OS.

Red or blue banner reading 'Secure Boot Violation: Invalid signature detected'
PC boots straight into BIOS setup instead of Windows
Open Step-by-Step Fix
Critical4 steps

NVMe boot drive missing from BIOS priority list after sudden power cut

An abrupt power outage or hard reset causes the NVMe SSD controller to enter a lockup or low-power recovery state, making the drive temporarily vanish from the motherboard UEFI boot menu.

PC boots straight into BIOS setup utility
M.2 slot shows 'Not Present' or 'Empty' in storage overview
Open Step-by-Step Fix
Critical4 steps

Power supply surge lockout (clicks once and requires AC unplug to reset)

The power supply internal supervisor IC triggers Over-Current Protection (OCP) or Short-Circuit Protection (SCP) due to an electrical surge or transient spike, latching into a protective shutdown.

Audible 'click' sound from the PSU when pressing power button, then silence
Power button does nothing on second press until power cord is disconnected
Open Step-by-Step Fix
Critical4 steps

Corrupted BIOS black screen recovery via USB Flashback

A failed BIOS update, interrupted flashing process, or incompatible firmware version has corrupted the motherboard SPI flash memory, leaving the computer unable to execute initial boot code.

Black screen with fans spinning indefinitely after flashing BIOS
No display signal, no keyboard capslock LED response
Open Step-by-Step Fix
Common4 steps

TPM configuration change prompt loop at startup

The motherboard firmware detects a new CPU or clear CMOS state, triggering a mandatory security confirmation screen to reset the Trusted Platform Module (fTPM / dTPM).

Screen displays 'A configuration change was requested to clear this computer TPM'
Prompts 'Press Y to reset fTPM or Press N to keep previous records'
Open Step-by-Step Fix
Critical5 steps

Uneven CPU cooler mounting pressure causing memory channel loss

Overtightening or unevenly torquing CPU cooler screws bends the LGA socket substrate, causing pin contact loss on delicate DDR5/DDR4 memory controller traces and preventing POST.

PC boots with 1 RAM stick in slot B2, but fails to POST with 2 sticks in A2/B2
Motherboard DRAM debug LED illuminates solid amber or red
Open Step-by-Step Fix
Common4 steps

DisplayPort monitor deep sleep no signal on boot

Modern high-refresh gaming monitors fail to wake from DisplayPort deep sleep power states during PC boot, causing the graphics card to report a VGA error LED due to absent EDID handshake.

Motherboard white VGA debug LED stays on
Monitor reports 'No DisplayPort Signal' and enters sleep mode
Open Step-by-Step Fix
Critical4 steps

PC randomly restarts or shuts down during heavy gaming with NO blue screen

Computer instantly goes black and powers off or restarts under heavy graphics load without creating a BSOD minidump.

PC instantly turns off as if power plug was pulled during heavy games
No blue screen, no dump file in C:\Windows\Minidump
Open Step-by-Step Fix
Critical3 steps

BitLocker blue screen asking for 48-digit recovery key on startup

Computer boots directly to blue BitLocker Recovery screen asking for 48-digit numerical key after BIOS update or hardware change.

Blue screen on boot: 'BitLocker - Enter the recovery key for this drive'
Triggered after motherboard BIOS update, TPM toggle, or SSD swap
Open Step-by-Step Fix
Critical4 steps

Black screen with no display signal after enabling Secure Boot in BIOS

Motherboard fails to output display signal or POST after toggling Secure Boot for Valorant / Windows 11.

No display signal immediately after enabling Secure Boot or changing PK keys in BIOS
PC turns on, fans spin, but monitor says 'No Signal'
Open Step-by-Step Fix
Common3 steps

New NVMe M.2 SSD or SATA hard drive not showing up in File Explorer

Installed a new solid-state drive or hard drive but it does not appear in 'This PC' or File Explorer.

New SSD installed but missing in File Explorer / 'This PC'
BIOS detects the SSD model name but Windows does not show the drive
Open Step-by-Step Fix
Critical3 steps

Laptop burning hot and battery drains while closed inside backpack (Modern Standby)

Laptop wakes up inside laptop sleeve or backpack, fans scream at 100%, and battery is completely drained.

Laptop burning hot to the touch when pulled out of bag
Battery drained from 100% to 0% while lid was closed
Open Step-by-Step Fix
Critical4 steps

Breadboarding a PC: Testing core components outside the case on cardboard

Isolate persistent short circuits, motherboard stand-off shorts, and non-POST issues by assembling bare minimum components outside case.

PC fails to turn on or clicks off immediately inside case
Motherboard suspected of shorting against metal chassis or standoff
Open Step-by-Step Fix
Critical4 steps

ASUS Q-LED and Q-Code Motherboard Debug Diagnostic Guide

Diagnose ASUS motherboard POST failures using 4-color Q-LED status lights (CPU, DRAM, VGA, BOOT) and 2-digit alphanumeric Q-Code hexadecimal readouts.

System fails to complete POST
Q-LED stays lit on Red (CPU), Yellow (DRAM), White (VGA), or Yellow-Green (BOOT)
Open Step-by-Step Fix
Critical5 steps

MSI EZ Debug LED Motherboard Diagnostic and POST Triage

Troubleshoot boot hangs and hardware initialization failures indicated by MSI EZ Debug LEDs (CPU, DRAM, VGA, BOOT) and 2-digit Debug Code LEDs.

MSI motherboard stops during power-on sequence
One of four EZ Debug LEDs remains constantly illuminated
Open Step-by-Step Fix
Critical5 steps

Gigabyte Motherboard Status Code Display and Debug LED Triage

Diagnose Gigabyte AORUS motherboard boot failures using onboard 2-digit 7-segment status codes and 4-phase diagnostic LEDs.

Motherboard hangs on 2-digit code such as C1, 54, 78, or 90
Diagnostic status LED stays illuminated without video display
Open Step-by-Step Fix
Critical4 steps

ASRock Dr. Debug Hexadecimal POST Code Triage

Decode ASRock Dr. Debug 2-digit hexadecimal POST codes to isolate CPU, memory, chipset, and GPU hardware initialization failures.

ASRock motherboard stops booting with 2-digit LED code displayed
POST stops at code 00, 19, 4C, 53, or d7
Open Step-by-Step Fix
Critical5 steps

Motherboard POST Beep Codes Diagnostic Guide (AMI, Award, Phoenix)

Interpret standard motherboard speaker acoustic beep codes across American Megatrends (AMI) and Award BIOS architectures to identify hardware faults.

Internal motherboard PC speaker emits beeping patterns upon power on
Screen remains completely black without video output
Open Step-by-Step Fix
Critical5 steps

Dell and HP Power Button Diagnostic Blink Code Triage

Decode OEM prebuilt desktop and laptop power button amber and white flashing LED patterns to troubleshoot hardware startup failures.

Power button flashes repeatedly in amber and white blink sequences
Fans pulse briefly but screen remains black
Open Step-by-Step Fix
Critical4 steps

ATX 24-Pin Power Sequence and PS_ON Green Wire Triage

Test ATX power supply startup sequences using the paperclip green wire PS_ON jump test and verify primary +12V, +5V, and +3.3V DC rail delivery.

PC does not respond at all when pressing the front power button
Zero lights, zero fan movement, and zero acoustic clicks from PSU
Open Step-by-Step Fix
Critical5 steps

PSU Power Good PWR_OK Signal Delay and 5VSB Standby Rail Timing

Diagnose power supply startup handshake failures where +5VSB standby power is present but the PWR_OK (Power Good) signal fails to assert within 100-500ms.

Motherboard standby RGB lights illuminate but pressing power button produces an audible click and zero fan movement
PC fan twitches for a fraction of a second then immediately shuts off
Open Step-by-Step Fix
Critical4 steps

Intel VMD and RST Storage Controller Missing Driver Windows Setup Fix

Resolve missing NVMe drives during Windows 10/11 installation on Intel 11th through 14th Gen systems caused by Intel Volume Management Device (VMD).

Windows Setup displays message: We could not find any drives. To get a storage driver, click Load driver
NVMe SSD is fully visible in motherboard BIOS but missing from Windows partition screen
Open Step-by-Step Fix
Critical4 steps

UEFI GPT vs Legacy CSM MBR Partition Table Boot Mode Mismatch

Fix boot failure where BIOS cannot detect a bootable drive due to mismatch between UEFI pure mode (requiring GPT) and Legacy CSM mode (requiring MBR).

BIOS boot menu reports: No bootable device found
Storage drive appears in BIOS hardware list but not in boot priority list
Open Step-by-Step Fix
Critical4 steps

EFI System Partition Corrupted BCD Rebuild Procedure

Repair corrupted or missing Boot Configuration Data (BCD) on the UEFI EFI System Partition using Diskpart and the bcdboot command in Windows Recovery.

Windows fails to start with error code 0xc000000f, 0xc0000034, or 0xc0000098
Screen displays: The Boot Configuration Data for your PC is missing or contains errors
Open Step-by-Step Fix