Constant BSODs (error codes in post)

Bit of a long story... Posting on behalf of a friend.

Just before Christmas my mates PC started acting up. He began to get random BSOD's (we couldn't find any way to trigger it or repeat the errors, it all appears random) . It kept getting worse and got to the point where he couldn't get into the system it would seize up at windows login and give him a BSOD. Sometimes it also have a BSOD with no text just a blank blue screen. We tried everything could think of to fix it but to no avail so it was left for a few months.

After saving up a he bought a new CPU and MOBO (his gfx card was already new and we tried running with onboard intel gfx to rule it out as the issue). All was fine for a few days but then the exact same thing has started happening again this evening. He got one BSOD and it deteriorated over roughly an hour from the occasional BSOD to even getting BSODs in Windows startup recovery. His PC also refused to post for like 15 minutes and has just now actually started powering up again.

Personally I suspect a driver issue but would not know how to actually diagnose this. As he cant even get into Safe Mode.

Some of the BSOD errors he is getting:
DRIVER_IRQL_NOT_LESS_OR_EQUAL
CRITICAL_PROCESS_DIED
KMODE_EXCEPTION_NOT_HANDLED
CLOCK_WATCHDOG_TIMEOUT

Things I know we have tried:
Running various things in CMD (sfc etc etc.)
He has replaced actual hardware
Reinstalled windows multiple times just for the problems to re appear
Driver repair
Tested his PSU