Need help with PC shutting off (seemingly) during heavy load and can't turn back on unless I fully unplug and wait.

[ProPigeon]

Hello dear forum users!
Please help me!
I have a problem with my PC randomly shutting off during gaming. It happens exactly like when there is a power outage, except the RGB lights on my RAM stay on. After shutting off, the pc seems to try to re-launch itself after like 2-3 seconds, but it fails and only the ram lights stay on. If I click with the mouse or push the power button (pushing once, not holding, If I hold the ram lights shut off too) nothing happens. Waiting for a few minutes will do nothing.
After this happens the only way I can get the PC to start up again is if I unplug the whole thing from the wall, push the power button to release any power left inside, wait for like 20 seconds and turn it back on. Then it turns on sort of like normal, it turns on once, shuts off, then turns on fully after 4-6 seconds (it does like a cycle) and then it is fully functional once again.
This shut-off (as far as I observed) only happens when I am gaming on demanding games, and after at least 2-3 hours of gaming, and randomly. Sometimes it won't happen for days, sometimes it happens twice a day etc.

Context:

Here are the specs: 
CPU: Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz (running at 4,7 Ghz oc-d, never had problems with that)
GPU: asus rog strix OC 2070 super
Ram: G skill tridentZ rgb 3200mhz 4x8gb
mobo: Asus ROG STRIX Z390-F GAMING
PSU: Be quiet! 750W Straight Power 11

+! Might be important: I have recently installed another set of the G-skill ram (2x8gb more, it is exactly the same model timing and everything, though it is about 4 years newer in terms of production)

Troubleshooting I've tried already: I thought that the addition of the new ram sticks may have just jumped over my 750W PSU's capabilities, so I lowered maximum CPU usage to 85% in windows power plan, and put nvidia control panel's power setting to optimal power savings instead of prefer max performance. (I have no idea if these do anything to really help me tho, I'm kind of a noob.)

If you have any suggestions or know what is going on, please tell me. Thanks all.

 

[DrMacintosh]

Losing power like a blackout is going to be related to the PSU. Time for a new one.

[podkall]

have you tried running just 2 sticks of RAM and seeing if it truly is the 4 RAM problem? (if the problem started happening after you switched to having 4 sticks of RAM)

[Whatisthis]

41 minutes ago, podkall said:

have you tried running just 2 sticks of RAM and seeing if it truly is the 4 RAM problem? (if the problem started happening after you switched to having 4 sticks of RAM)

Probably wouldn’t be RAM if you can’t immediately reboot - that’s the PSU throwing a protection circuit. The fact it’s happening under load all but confirms the issue.

 

To fully confirm, you can run just furmark. It shouldn’t crash with just gpu load. Then run just cinebench. This is purely cpu load. Should be fine again. Now run both at the same time and it should trip the PSU.

[ProPigeon]

13 hours ago, podkall said:

have you tried running just 2 sticks of RAM and seeing if it truly is the 4 RAM problem? (if the problem started happening after you switched to having 4 sticks of RAM)

I didn't but I ran the memory diagnostics tool and it showed no errors. But yes I think it did start just after I installed the new ram. I maybe should still try removing them!

 

 

12 hours ago, Whatisthis said:

Probably wouldn’t be RAM if you can’t immediately reboot - that’s the PSU throwing a protection circuit. The fact it’s happening under load all but confirms the issue.

 

To fully confirm, you can run just furmark. It shouldn’t crash with just gpu load. Then run just cinebench. This is purely cpu load. Should be fine again. Now run both at the same time and it should trip the PSU.

Can you explain what's a protection circuit?
I will try running furmark and cinebench!

[podkall]

7 minutes ago, ProPigeon said:

Can you explain what's a protection circuit?

I will try running furmark and cinebench!

it works similarly to circuit breakers houses and flats use