PC restarts randomly

[InCrt]

Hi everyone!

 

This is an issue that I have been dealing with (ON and OFF) for a couple of months now, where my pc just shuts down and then reboots by itself.

It happens while doing just about everything, gaming, watching videos (mostly on youtube), listening to music, it even happens when I'm afk and the pc is doing nothing.

In some extreme ocassions it will restart twice, very rarely even three times in a row. This last time (today) after the third it didn't even restart at all, it completely shut down. Upon restarting it myself I got the message that it had previously failed to boot and to press F1 to run bios setup.

What is odd about it tho, is that it can manifest constantly for days and then at times completely disappear for weeks. Making it extremly hard to diagnose what's causing it.

 

Here's my build:

 

PSU - Corsair AX-860 80+ Platinum
Motherboard - ASUS ROG Strix Z370-F Gaming
CPU - Intel i7-8700K @ stock
Cooler CPU - Corsair iCUE H150i RGB PRO XT 360mm
GPU - MSI GTX 1080 Armor OC 8GB GDDR5X
Memory - Corsair Vengeance RGB Pro 16GB
SSD - Samsung 850 EVO 500GB
HDD - Seagate Barracuda 2TB and Toshiba DT01ACA 3TB
 

And here's what I've done so far trying to figure out was is causing this:

 

- Limited GPU temp on MSI Afterburner to 80º. Did nothing, restarts still happened.

- Ran memtest86 on each stick of RAM individually and no errors were found.

- Ran OCCT to test the PSU for 1 hour and no errors were found.

 

Also worth mentioning, for about 3 weeks I have been turning the PSU power off before going to sleep. Completely shutting down any power to the PC while I'm sleeping.

That seemed to help for that duration, since I didn't get a single random restart. However, yesterday the restarts came back, and this time it's much worse.

I had 4 restarts yesterday and today I'm at the third already, today being all consecutive restarts too. The last one being a complete shutdown and fail to post.

 

I'm lost as to what's causing this, if I was to guess I'd bet on it being the PSU. Which is still in warranty, till May of this year. But I'm not sure if it's worth sending it to RMA, since the restarts are so random that it may not even happen while Corsair is testing the PSU.

 

Ideas? Any help is welcome. Thank you in advance!

[InCrt]

15 minutes ago, Essm1971 said:

For me, replacing a PSU solved the problem!

Were you having the same issue? Random restarts at doing just about anything and even while afk?

[InCrt]

You were right Essm1971, my PSU died 2 days ago. Got a new the day after and no restarts so far.