ProteusCortex

Although that would be good for future-proofing (and seems that the future is near, as more and more game benefit from >8GB RAM), I don't think it is necessary right now. I would wait for RAM prices to drop a bit, because they are more expensive than their weight in gold.

The main issue was solved. I initially thought that it was the power supply and RMA'd it, but when using my old power supply I encountered the same issue and thought it must be something else. My GPU (Sapphire Radeon RX580 Pulse Edition) requires a PSU with a minimum rating of 500W. My old PSU is a Corsair CX500 with a 500W output rating, so I thought it should be OK. Turns out my old PSU has some issues of its own and can no longer reach its rated output of 500W, which my system seems to pull at maximum load. This is because I added another 300W PSU, just to power the GPU and everything could be stressed to 100% without any issues. So I will just wait for the RMA of my main PSU to go through and everything should be fine. Thank you all for your help. You really stirred me back to the correct solution.

I already did that. The CPU (overclocked @ 4.5GHz) would run OCCTPT's Linpack test with AVX, on all logic cores and using 90% of RAM for more than an hour, reaching a maximum of 70°C with no issues whatsoever. Only when pushing the GPU I encountered issues. After adding a second PSU that powered only the GPU I could run all of OCCTPT's tests (even the "Power Supply" test) without the system shutting down.

I bought it in 2017 brand new. So it doesn't really matter when it was first released (the P2 version was released in 2016, I think), because electronics have a huge shelf life. It's only when electrolytic capacitors are involved that you have to let them powered without load for a bit and that applies mostly to electric motor drives, that really push them to the limit. So yes, it was as new as it gets. I was powering 2 GPUs with it when I bought it and for about 10 months (an RX480 and an RX580), so I don't think there was an issue until recently. I also had a UPS for the last 11 months, so there shouldn't be any issues with the grid power quality.

Well, in short: - My problematic PSU is an EVGA Supernova P2 @ 850W and has handled 2 GPUs in the past. - The old PSU is a Corsair CX500 @ 500W. Nothing off ebay. - Pretty much nothing gets to heat up because no benchmarks can actually run. - Made a Frankenstein's Monster with a second PSU (that one is indeed no-name, but it works fine) to power the GPU only and everything seems to be OK. - I'll just wait for the problematic PSU to be replaced.

I measured the grounding from the outlet to the UPS. Also between the outlet and the case. Everything seems to be OK. Couldn't measure voltages on the motherboard, though. My hands are not that steady.

OK. It looks like the "minimum requirements" for the GPU's PSU are not that accurate or my older power supply cannot actually output 500W (which is also the minimum PSU requirement for the GPU). The fact that it couldn't handle the older GPU shows that it has its issues too...

Never touched the VRMs. I have also stress tested the CPU and it reaches a maximum of 70°C and the system seems stable. Also the last temperature I get to see for the GPU is 50°C before the system shuts down. I haven't checked the VRM temperature in any way.

The PSU is about a year old. I also tested my old one and I still gave issues.

Any idea on how to test this?

No. No overclocking for the GPU whatsoever. And for the CPU is just the default OC from the mobile (about 5%).

Hello, I have quite a strange issue. When pushing my GPU to 100% my system just shuts down and then restarts. The power supply is more than enough (850W) and it used to power 2 GPUs at full load with no issues whatsoever. What I have tested so far is: Switched to another power supply (just to be sure). Switched to an older GPU (nvidia GeForce GTX 650Ti). Switched PCIe slots (just in case there is an issue with the mobo's power supply to that slot...?) Tried the latest "recommended" drivers from AMD. Every time I'm running FurMark and it doesn't even get to show the furry donut. The system just shuts down. Any ideas on how to narrow it down?

Found the issue. My display was connected using DisplayPort and for some reason it reports to the GPU that it has audio. Thus the audio output was rerouted to the GPU.

So. The board was replaced. Got a new one. Same issue. Only difference is that when I remove both GPUs, I get sound on the left speaker.

I tested the speakers on other sources and tried with 2 different sets of headphones. I'm sure it wasn't a driver issue, because it would work with the other OSes that I tested. Thanks for your help, but the motherboard died completely and I RMA'd it again.