No GPU Post Error (RX 6600)

[LarveyRGH]

Hi all, recently built myself a new PC - its been great for the first month - but recently I've been having a weird glitch and I'm wondering if anyone would be able to help.

 

Issue: Every time I turn on my PC from cold (i.e first thing in the morning) - I get a "No GPU" post error. My motherboard uses the HDD LED as a diagnostics LED, and it does a slow flash every 1/2 seconds. With enough mucking about, unplugging my display port, unplugging power, plugging everything back in, eventually it'll come back to life - PC will power up as normal, and no more issues. Next day, same thing happens. It was only doing this up until about a week ago, me being naive thinking it'll solve itself - but no.

 

I originally thought maybe its because I've gone to Debian, but apparently this isn't the issue as I've tried going to another Linux distro (Pop_OS) and had the same issues. I have updated my motherboards BIOS, set it back to factory by clearing the CMOS, etc. All temporary fixes.

 

ASUS Q-LED Guide I followed: https://www.asus.com/support/FAQ/1042678

Motherboard troubleshooting guide: https://www.asus.com/uk/support/FAQ/1042632

 

My PC build (PCPartPicker)

 

One would assume that this is a GPU issue? What do we all think? I'm very much stumped. Thank you all.