PC random reboots

[case sensitive]

I signed up years ago but never posted before so hello

 

Since around September last year I've been getting random reboots and can't figure out the cause.
The PC will just power off and instantly reboot, no BSOD etc. and no errors in Event Viewer aside from the generic "previous system shutdown unexpected".

 

I only notice this when playing one game (Runescape 3) however that's 90% of what I do with my PC so I'm not sure if related.
It isn't a very demanding game on the CPU/GPU and I'm often doing other things at the same time (watching YT, playing Civ6 which is the only other game I play) but I've never had one when RS3 isn't running.

 

It will happen around once a day on average but sometimes multiple times in quick succession.

 

System specs:
Ryzen 5950x
MSI MEG x570 Unify (currently BIOS AL1 but going to try updating next, I previously updated it after the reboots started last year)
G.Skill F4-3200C14-16GTZ (32GB kit)
RTX 2080Ti
Corsiar RM750x
SN850x 2TB (brand new, just replaced a failed SX8200 pro, the reboots happen with both)

 

Cooling-wise I'm running a custom loop that definitely needs a clean-out but temperatures aren't out of control (low-mid 70s on CPU, mid-high 50s on GPU hotspot).
Nothing is overclocked (XMP is active but I've tried without too).

 

So far I've tried the following:
Swapping PSU
Disabling XMP
Disabling C-states
Small increases and decreases to SOC voltage and others related to memory/IF but everyting is back to stock now
and...

 

Disabling fTPM (I saw some related errors in Event Viewer and tried it on a whim).
I thought this fixed it, I went about 6 months without a random reboot but they started again a couple of weeks ago.

 

I've ran several stress tests overnight whithout issue as well as a mixed-load test for the CPU (can't remember what it's called)
OCCT GPU with error detection
Memtest86 and TM5
Prime95 blend
I think I also ran F@H on GPU with P95 on CPU because I saw somebody suggest that

 

Any thoughts?
I'm out of ideas

[Busbar man]

Not sure if this help but try reseating all the rams slot and ensure ur gpu is using 2 or 3 power rail instead of dairy chain the cable.

[leclod]

you could check windows by : open cmd as administrator and run both

DISM.exe /Online /Cleanup-image /Restorehealth (this can last a while)

and

sfc /scannow

you could reinstall windows

You could reseat/replug everything carefully, also on psu side.

Reset your bios

A pity you don't have an igpu.

 

 

Edited November 22, 2025 by leclod

[Bjoolz]

Have you checked in Event Viewer if it has any WHEA events? In Event Viewer, go to Windows Logs → System. On the right hand side select Filter Current Log. In the Event Sources dropdown menu, select WHEA-logger and click Ok to apply the filter. Highlight them if it has any, right click and save. Attach the .evtx file here. 

[case sensitive]

Thanks for all the suggestions.

 

13 hours ago, junweigoh123_ said:

Not sure if this help but try reseating all the rams slot and ensure ur gpu is using 2 or 3 power rail instead of dairy chain the cable.

I'll try reseating RAM and connectors tomorrow, I feel like this is something I'd have done early on but definitely worth double checking.

PSU is single-rail as far as I can tell so shouldn't be an issue there.

 

10 hours ago, leclod said:

you could check windows by : open cmd as administrator and run both

DISM.exe /Online /Cleanup-image /Restorehealth (this can last a while)

and

sfc /scannow

you could reinstall windows

You could reseat/replug everything carefully, also on psu side.

Reset your bios

A pity you don't have an igpu.

 

SFC and DISM both come back clear. This has persisted through multiple clean Windows installs across 3 different SSDs (2x NVMe and 1x SATA).

I'll reset and update BIOS tomorrow as there is a newer version available anyway.

I'll try swapping my old R9 290 back in as I still have that lying around.

 

6 hours ago, Bjoolz said:

Have you checked in Event Viewer if it has any WHEA events? In Event Viewer, go to Windows Logs → System. On the right hand side select Filter Current Log. In the Event Sources dropdown menu, select WHEA-logger and click Ok to apply the filter. Highlight them if it has any, right click and save. Attach the .evtx file here. 

No WHEA events at any time or any other Event Viewer errors before the restart.

[Bjoolz]

52 minutes ago, case sensitive said:

Thanks for all the suggestions.

 

I'll try reseating RAM and connectors tomorrow, I feel like this is something I'd have done early on but definitely worth double checking.

PSU is single-rail as far as I can tell so shouldn't be an issue there.

 

SFC and DISM both come back clear. This has persisted through multiple clean Windows installs across 3 different SSDs (2x NVMe and 1x SATA).

I'll reset and update BIOS tomorrow as there is a newer version available anyway.

I'll try swapping my old R9 290 back in as I still have that lying around.

 

No WHEA events at any time or any other Event Viewer errors before the restart.

Power would be the main suspect then. The PSU, power cable, power strip (if used) or unstable power from the wall.