Okay so after a day or so of testing various components with benchmarking tools this is what I discovered:

Prime95, Cinebench, Heaven Benchmark, Memtest86 and monitoring with HWInfo64, HWMonitor, Afterburner and even CrystalDisk for checking SSDs - none of which crashed my Pc during testing and none that showed any signs of corrupt memory or temp spikes.

I was on the cusp of changing the PSU, when I noted that the voltages looked fine in HWMonitor and never send to fluctuate throughout testing, so to me looked stable.

I decided in a 3 hour session of Diablo 4, but this went by without a hitch and did not crash the PC.

Stupid I know, but as a last resort before ripping everything out I decided to delete BG3 completely (excluding saves that I backed up), and reinstall it.

As I booted up steam before I uninstalled BG3 I did notice a small patch (after the major one downloaded) but I deleted the install all the same and then started the download over.

Whilst I did this I cast my mind back to the time of the last shutdown/crash and trawled through the event viewer log. I found immediately before the “6008 error the system shut down was unexpected” (created when I booted up the PC after the crash) that there were 3 entries of a particular registry key requesting local activation permission for the COM Server application with CLSID xxx and APPID xxx that permission was not granted.

I took a hell Mary and decided once BG3 (if this was involved any way) reinstalled I’d create a desktop shortcut and always right click and run as administrator.

I’ve now had 2 5 hour sessions with no crashes, leading me to believe:

The delete and fresh reinstall could have fixed it.
The “run as administrator” could have fixed it.
The random Larian update could have fixed it.
It may not be fixed and will reappear later.

Either way I wanted to update you guys. I haven’t replaced anything yet but as a reward (even though it didn’t need it) I cleaned the PC and all fan blades today to keep it happy.

I’ll let you know if it happens again, if it doesn’t I hope what I’ve wrote helps one of you also having the issue.

Last edited by SinisterCP; 27/08/23 10:48 PM.