Question My video signal going away randomly/GPU restarting

Jan 24, 2021
Hey Yall. I built myself a PC about a week and a half ago. I've already encountered an issue. For some reason, my video signal goes out randomly. When it does, I can hear the fans of my GPU going lowder and then instantly going back to normal for like a second. Then, I just have to plug out the HDMI, plug it back in, and it's all good. Signal restored, and I can continue doing what i was doing. It's not the HDMI, I tested other cables already. It's not the monitor, when the signal goes out it tells me "No HDMI connected".

My specs are the following:
CPU : Ryzen 5 3600 6-Core Processor 3.59 GHz
RAM: G.Skill DDR4 3200 4x8 gigs
Motherboard: ASRock B550M PRO4
GPU: GAINWARD Phoenix RTX 3070
PSU: Gigabyte GP-P750GM, 80 PLUS® Gold, 750W, PFC Activе

Now, at first I thought it was the GPU turning on and back off again. But, my PC doesn't shut down and it doesn't blue screen. So it can't be that. I already know it's not the cable and the monitor works fine. I only really have one theory, the power. As in, the actual electricity powering the card itself. The power at my current place is...not good. On the day that we got the PC up and running with a friend of my, I had it, the monitor, 2 active speakers and a soundcard all connected to the same extension chord. When I connected a 2nd chord for an electric radiator, the power went out cause a breaker went down. Guess it was too much power for it. This hasn't happened since and I've now connected the PC directly to the wall socket. But, needless to say, the electrical work here isn't the best. That's the only theory I have.

Now, before I made this post, I was watching a movie in MPC, and when this issue happened again and I repledged the HDMI , this time, MPC gave me an error, here it is: View:

Maybe this is a driver issue, but yesterday i reinstalled the Nvidia drivers. So I really got nothing at this point. Maybe it has to do with the Hz of the monitor? I'm running it at 144 Hz. I don't know. Anyone got any ideas?