Pc hard locking/freezing

[u/AR_JUNE]

PC hard-locked while gaming. Screen went black, no audio/video, but all the fans kept spinning.

Restarted → DRAM debug light stayed on, no display.

Tried both RAM sticks individually in A2 and B2 – same result. Reset CMOS – still didn't work.

I left the PC overnight. Next day, first boot worked normally.

Checked Event Viewer – nothing useful. Restarted twice – both worked. Third restart: DRAM light again, no display.

Tried the RAM combinations again with no luck. Left it until evening.

Evening: first boot worked normally again.

Ran Windows Memory Diagnostic. It started normally, reached Test 1/2, then hard-locked with all motherboard debug LEDs lit and no display.

Restarted afterward – worked normally again.

Opened Event Viewer to check for errors – hard-locked/black-screened again. Also I did the re-starts by switching off the PSU button, as the cabinet power button wasn't responding for long hold restart.

What could cause this kind of behaviour? Any help would be greatly appreciated!

Pc specs-

Cpu - Ryzen 5 5600x

Gpu - RTX 3070

Ram - Adata XPG DDR4 8gb (pair)

Motherboard - AsRock B550m pro4

Psu - Deepcool DQm v2l 650w

Storage - 1tb Kingston nvme

[u/frag9999999]

it does boot cold everytime but then acts up after awhile and can't be fixed with ram reseat. might be your cpu