RTX 3080 PC randomly restarting

[Ricot_Shot]

I have a MSI RTX 3080 Gaming Trio for about 2 months or more. My PC recently started to randomly restart. It feels like the power suddenly cuts out, everything from the monitors go black instantly and after 1second the CPU restarts on its own. I am certain that it doesn't depend on load because it doesn't restart if I stress but it sometimes restarts when I am just browsing the web. Sometimes when I start my PC in the morning it won't start immediatly it fails to start a couple of times. I have to switch off the main power outlet and turn it on again to make my PC start. The restart generally happens around once a day. 

Here is my Full specs:
-CPU:  intel i7 8700
- Mobo: Asus Z370-P Prime
-GPU: MSI RTX 3080 Gaming Trio
-PSU: Thermaltake Toughpower GF1 850W
-CPU Cooler: Corsair H100i Platinum
-HDD: Toshiba 1TB and Segate Baracuda 4TB
- SSD: Intel SSD 256GB and Samsung EVO 970 plus 512GB
- Triple Monitors

* My Gpu has 3 PCIe sockets, the cables from my PSU had 2 headers on each wire so I used 3 headers from 2 wires. 

How can I pin down the source of the problem ? Thank you

[ObsidianAura]

I saw similar behaviour a while back when a GPU was overheating. I reapplied the thermal paste and it went back to normal, I'm not suggesting you do that, your cards too new for that to be a problem and its a somewhat risky thing to do, but may be worth installing a program that logs temperatures for you. 

[dilpickle]

It's almost certainly a bad mobo.

[Ricot_Shot]

1 hour ago, ObsidianAura said:

I saw similar behaviour a while back when a GPU was overheating. I reapplied the thermal paste and it went back to normal, I'm not suggesting you do that, your cards too new for that to be a problem and its a somewhat risky thing to do, but may be worth installing a program that logs temperatures for you. 

My GPU temps are usually around 60 degs when this happens. So I don't think temp is the issue in this case. 

[Ricot_Shot]

1 hour ago, dilpickle said:

It's almost certainly a bad mobo.

Yeah that could be possibility as it's one of the oldest components in my setup. Is there some way I can test it ? From BIOS or any software?

[dilpickle]

3 hours ago, Ricot_Shot said:

Yeah that could be possibility as it's one of the oldest components in my setup. Is there some way I can test it ? From BIOS or any software?

Only way to test is to swap it out. Unless you're an electrictrical engineer with some testing equipment.

 

 

I had an Asus mobo with the exact same problem. The reboots got more and more frequent until it was even rebooting on the bios menu.

 

I gave it to someone who put it in his system and he had the exact same problem. That's how I knew it was 100% the mobo.

[Ricot_Shot]

24 minutes ago, dilpickle said:

Only way to test is to swap it out. Unless you're an electrictrical engineer with some testing equipment.

 

 

I had an Asus mobo with the exact same problem. The reboots got more and more frequent until it was even rebooting on the bios menu.

 

I gave it to someone who put it in his system and he had the exact same problem. That's how I knew it was 100% the mobo.

Coincidentally I do happen to be an undergrad electrical engineer. Haha. Thanks for the help man.

[Ricot_Shot]

Turns out it was my Casing's power switch !!!