Ok so this is a tough one. This isn't about my computer, it's about my friends', but he doesn't speak english so he asked me to make this post. So first he started having a problem where his pc would randomly shut down, but the ventillators would keep spinning but the screen would be black and nothing would work. We couldn't figure out the problem, but it was time for an upgrade anyways so he bought completely new motherboard, memory, and cpu. The problem didn't go away, so he bought a new power supply. The screen kept randomly going dark and the pc wouldn't respond to anything. We tried reinstalling the windows multiple times, tried keeping the computer in the boot menu (the problem still happened!), tried updating the bios (which was a crazy risky thing to do), the problem still exists. The only things that we didn't change was the graphic card and the hdd and the ssd. So he borrowed a video card (from a working computer). So to recap we switched the botherboard, cpu, memory, graphics card, power supply, the power supply cable and the problem still exists. We have literally no idea what else to do.
Sadly he had some bad experience with professional service, so he doesn't want to ask one.
Our only theories left is that somehow the electricity in the house isn't stable enough (idk man)
Or something with the case. Any help would be appreciated (sorry for grammar mistakes)
This thread is now locked and can not be replied to.