So... My PC consists of components that were bought in 2015, EXCEPT the PSU which is around 10 years old...
Everything was working absolutely fine until November 2021, when my pc randomly started to shut off by itself and then automatically turn back on. It happened like once 2 weeks.
Then december started... the random shut offs started to happen more frequently... that's where I found out... when I start a modern game like Genshin Impact, Diablo 2 Resurrected etc., the PC turns off after 30 seconds... But if I just chill on the internet or play retro games like Heroes of Might and Magic 3, nothing happens... even if the PC was turned on from morning to late night hours, the PC wouldn't randomly shut off... So my obvious guess was that PSU was old and needed a replacement.
I had to wait a week to get to my new PSU, so I was still using my PC with the "faulty" PSU, all I did was browse internet and play the mentioned retro game... nothing else... didn't have a single random shut down.
So I got my new PSU... replaced it with the old one... Everything worked fine. I could play the modern games again for as much as I wanted.... for 2 days that is.... So on the second day the PC was running pretty much for a whole day, browsing, gaming, the usual stuff...
But THEN, around 3:00 AM, not only did PC randomly shut off, but now it's not turning on at all.
I tried to take out the power cable, put it back in, turn the switch off/on, the typical things that people suggest you to do on the internet... nothing worked, at all. Just a small clicking sound from the PSU when I pushed the power button on my PC case.
I tried to plug back in the old PSU, just to check if the PC would turn on, all I got was a small light for a second from the motherboard that's usually just shining there while the PC is on (no, not the danger blinking light), not a single fan was spinning.
I held the power button for 20 seconds, THATS when I got the blinking blue light at the bottom of the motherboard for a few minutes.
I took off GPU (GTX 970) from the motherboard, pushed the power button, the pc started to work (the cables were plugged into the motherboard with an integrated graphics card, i5 4690k ). That's when I tried to put into the motherboard an old GPU (like around 10 year old gpu) just to see what would happen with monitor cables inserted in. The PC was working but nothing was shown on the screen.
To sum this up:
with GTX 970 inserted in, nothing happens, the pc doesn't turn on.
with an old GPU, the pc turns on but nothing is shown on the screen.
I left the GPU slot empty and inserted a DVI cable into the motherboard... Everything works.
I tried it with both PSUs, both work the same.
So what is the problem now?
Can't the motherboard handle GPUs anymore? I tried to insert both GPU's in both GPU slots, the problem stays the same, so it can't be the slot or the GTX 970 itself that is damaged (I've never done overclocking, nor pushed the limits with graphics in video games...) I'm just guessing at this point though.
System components:
CPU - i5 4690k (Hyper 212 EVO CPU Air Cooler )
GPU - GTX 970 EVGA FTW
RAM - 16GB (2x 4gb & 1x 8gb) 1600 mhz
Motherboard - MSI Z97 GAMING 3
HDD - Seagate Barracuda 1TB
PC Case - Cooler Master HAF 922
OLD PSU - INTER-TECH SL-700
NEW PSU - GIGABYTE P750GM