So I was changing the case fans, after I put everything back together, I forgot to plug in the power for the GPU. I turned the pc on and I saw the white LED on GPU power port lid up and heard the fan spins like crazy (I don’t know if it was the CPU fan or the GPU fans), I panicked and immediately turned off the power supply.
Everything happened in less than 2 seconds, I’ve run some stress tests and gamed for a few hours and nothing bad happened (yet?) so I assumed everything is still fine (for now?).
What happens if I had left it on like that for longer? And why did the fan ram up like that?
Depends on the GPU. Usually the GPU just doesn’t work at all. Some older models had a buzzer built in and would beep at incredibly loud volumes at you.
My old GTX 1080 would run just fine but with a 75 watt power cap. But that’s more of an exception since the 10 series were so incredibly efficient. Some lower end cards might do the same thing.