HP Laptop not starting

[Albe_2010]

Hello everyone, I have a problem with my laptop. I bought it two years ago (it's new) and used it until one day the screen started making strange things (lines, flashing, strange colors, flickering) and blue screened (HYPERVISOR ERROR). Then the PC didn't turn on. I tried two hard resets, both worked. While I was running diagnostics, everything froze and now I'm back at the start. When Windows 11 started again, I got the same BSOD two times: "KMODE EXCEPTION NOT HANDLED".

Hard resets don't work. Removing SSD, RAM, battery and network card doesn't work. Restoring the BIOS with a USB flash drive and Windows + B or V doesn't work. No error codes, nothing. When I remove the RAM the PC shows a Caps Lock error, so it isn't dead. Oh, and starting the PC only with the original AC adapter doesn't do anything. The screen doesn't have signal or power (no backlight). External display doesn't work.

The laptop bootloops with occasional white screen flashing and no hard drive activity. But hard resets don't work anymore.

Please help me. I got this laptop as a gift. It can't be dead after two years! Thanks for the help.

[A_Gayathri · Accepted solution]

Hi @Albe_2010,

Welcome to The HP Support Community.  

Thank you for posting your query, I will be glad to help you.

I understand you are facing issues you're facing with your HP 14-Dq0000 Laptop PC. Let's try a systematic approach to troubleshoot and possibly resolve the problem. Here are some steps you can follow:
 

Preliminary Checks

Power Cycle the Laptop:

• Disconnect the laptop from the power adapter.
• Remove the battery (if removable).
• Press and hold the power button for 15-20 seconds.
• Reconnect the battery and power adapter, and try to power on the laptop.

Check the Power Adapter:

• Ensure the power adapter is working correctly by testing it with another compatible HP laptop if available.
• Inspect the power cable and adapter for any visible damage.

Hardware Diagnostics

Remove and Re-seat Hardware Components:

• Disconnect the power adapter and remove the battery.
• Open the laptop and carefully re-seat the RAM modules and SSD.
• Ensure all connections are secure.

Test with Minimal Hardware:

• Try booting the laptop with only the essential components: one stick of RAM, SSD, and power adapter.
• If you have multiple RAM sticks, try booting with one stick at a time in different slots.

BIOS and Firmware 

Reset BIOS to Default:

• Disconnect the power adapter and remove the battery.
• Locate the CMOS battery (small coin-cell battery on the motherboard) and remove it for a few minutes.
• Reinstall the CMOS battery, reconnect the main battery and power adapter, and try to power on the laptop.

BIOS Recovery:

• Create a BIOS recovery USB drive using another computer.
• Plug the USB drive into your laptop.
• Hold the Windows + B (or Windows + V) keys and press the power button.
• Release the power button but continue holding the Windows + B (or Windows + V) keys until you hear beeps or see a BIOS recovery screen.

Software Diagnostics

Boot into Safe Mode:

• If the laptop powers on, repeatedly press the F8 key (or Shift + F8) during startup to access the Advanced Boot Options.
• Select "Safe Mode" and see if the laptop boots.

Run Windows Memory Diagnostic:

• If you can access the Advanced Boot Options, select "Windows Memory Diagnostic" to check for memory issues.

External Display

• Since you've mentioned that an external display doesn't work, double-check the connection and ensure the correct input source is selected on the external monitor.
• Try different cables and ports if available.

Refer to this document:  HP 14-dq0000 Laptop PC series User manual

I hope this helps. 

Take care and have a good day.

Please click “Accepted Solution” if you feel my post solved your issue, it will help others find the solution. 

[Albe_2010]

Thanks for your answers! This laptop doesn't have a CMOS battery, so the main battery does everything. A hard reset isn't working. Booting the laptop with bare minimum components doesn't solve the problem. BIOS recovery isn't supported by the laptop, I think (I have already tried with a USB recovery drive). The power adapter is original and it works. Reseating every single cable and component doesn't solve anything, so today I ordered a new stick of RAM because I think that's the problem. Again, thank you for your help!