Question Clevo X170KM-G – Powers on but no display, even after full stripdown. Is motherboard replacement the next step?

[BorislavSE]

Hi all, I am troubleshooting an issue with my Clevo X170KM-G laptop (Intel i9-10900K, RTX 3080), which I have had for 4 years. It was working perfectly yesterday, but today it suddenly refuses to boot properly.

When I press the power button:

• The laptop turns on
• Fans spin up
• Keyboard lights come on
• …but the screen stays completely black and nothing shows up on an external monitor either (HDMI or DP).

There are no POST beeps, no BIOS splash screen, and no backlight flicker. It just sits there and occasionally changes fan speeds.

Here is everything I have tried so far to no avail:

• EC reset (held power button for 1 minute with battery and charger disconnected)
• CMOS battery removed for 15+ minutes
• Removed and tested RAM individually in Slot 1 (tried different sticks)
• Removed SSDs and Wi-Fi card
• Removed dedicated GPU to force fallback to iGPU
• Powered on with only: motherboard, CPU, 1 RAM stick.
• Repeated CMOS reset in this minimal config

I am now leaning toward the motherboard being the fault. It could also be a CPU failure, but that would be less likely.

Any second opinions would be hugely appreciated. I am no expert, and I want to confirm I am not missing something.

 

[Lutfij]

Welcome to the forums, newcomer!

Seems to me like the motherboard might be having a short or the BIOS has ended up corrupt on the motherboard. For the latter, you can use a CH341A BIOS programming toolkit and reflash the BIOS. For the former, you will need to use a multimeter and identify the short or voltage injection to see what component is causing said short.