Here is the user's .blend file:
https://blenderartists.org/t/why-blender-causing-my-pc-to-restart/1190036/61

Although everything indicates that it could be a hardware problem, the strange thing is that the user claims to have the problem with 4px Tile Size in Volumetrics, but the problem does not occur with 2px Tile Size that is more GPU demanding.

In T71481#808747, @YAFU (YAFU) wrote:

Here is the user's .blend file:
https://blenderartists.org/t/why-blender-causing-my-pc-to-restart/1190036/61

Although everything indicates that it could be a hardware problem, the strange thing is that the user claims to have the problem with 4px Tile Size in Volumetrics, but the problem does not occur with 2px Tile Size that is more GPU demanding.

Yes, that's weird, im guessing it can be a hardware issue, cause also when im exporting 8k textures from substance painter with so many layers, pc restarts.
I only found these 2, but stress testing, playing games, also other 3d software like Marmoset or unreal engine doesn't cause any restart.
What do you think?

I'm not saying it is, but this has all the trademarks of a RAM issue, unexpected but repeatable failures across multiple applications with added weirdness. It really depends on what is loaded into memory and where. So might not be critical to some apps/games but others cause issues.

Make sure that you are not overclocking RAM (or anything else for that matter, it cannot be suppported here). Make sure your BIOS is up to date, default all settings, auto-detect if it has that feature.

Run a mem test, but be aware that the a PASS result can't always be trusted, but a FAIL will confirm your suspicion of it being hardware. Personally I prefer the manual method:

If you have more than one stick of RAM, remove one and test, if it doesn't crash you have found the culprit. If not then swap and try again until you run out.

In T71481#808760, @gbayliss (gbayliss) wrote:

I'm not saying it is, but this has all the trademarks of a RAM issue, unexpected but repeatable failures across multiple applications with added weirdness. It really depends on what is loaded into memory and where. So might not be critical to some apps/games but others cause issues.

Make sure that you are not overclocking RAM (or anything else for that matter, it cannot be suppported here). Make sure your BIOS is up to date, default all settings, auto-detect if it has that feature.

Run a mem test, but be aware that the a PASS result can't always be trusted, but a FAIL will confirm your suspicion of it being hardware. Personally I prefer the manual method:

If you have more than one stick of RAM, remove one and test, if it doesn't crash you have found the culprit. If not then swap and try again until you run out.

I had another 2 slots of ram, also tried another ram from the local shop i visited they also tested with another 550W PSU. Still pc was restarting.
Is there any chance that GPU's Vram is causing this issue ? Or the VRMs? some people saying it can be the memory and some saying my vrms is dying, (don't know which one GPU or MOBO)

Could you provide a simple file demonstrating the problem?

In T71481#809775, @Germano Cavalcante (mano-wii) wrote:

Could you provide a simple file demonstrating the problem?

Yes, check the first reply

I can't reproduce the problem, and my setup is not so different from yours:

Operating system: Windows-10-10.0.18941 64 Bits
Graphics card: Radeon (TM) RX 480 Graphics ATI Technologies Inc. 4.5.13559 Core Profile Context 26.20.12028.2

Be sure to install the latest GPU drivers.
Also test with one of the latest builds: https://builder.blender.org/download/

In T71481#810246, @Germano Cavalcante (mano-wii) wrote:

I can't reproduce the problem, and my setup is not so different from yours:

Operating system: Windows-10-10.0.18941 64 Bits
Graphics card: Radeon (TM) RX 480 Graphics ATI Technologies Inc. 4.5.13559 Core Profile Context 26.20.12028.2

Be sure to install the latest GPU drivers.
Also test with one of the latest builds: https://builder.blender.org/download/

Well this can also be hardware issue though I am not sure.
I need to troubleshoot my hardware first

In T71481#815210, @Philipp Oeser (lichtwerk) wrote:

More than a week without reply or activity. Due to the policy of the tracker archiving for until required info/data are provided.

I troubleshooted my whole system, i also used another rx 580 to test it, still it was restarting, i sent the file to one my of friend who's using a gtx 1050ti and didn't face any issue, i can't find any nvidia gpu to test on my system to be sure if it's really a gpu issue or not.
But looks like it's hardware/software combination issue to me, since it's not restarting when using 2px tiles size but only restarting when i'm using 4px only in that scene, not any other scene.
So now i'm not sure if i should report this to blender or AMD