Had this pc for about 2 years now, and it recently locked up and the screen got pixelated. Afterwards it would do the same thing every boot so I assumed the video card had overheated. I cleaned the fans and and everything out with compressed air (and a lot of dust did come out, especially out of the power supply). Still had the issue so I swapped video cards to an older card (one that had issues before) and everything boots now and I don't lock up.
The problem I am having now though is that the computer seems to be running much slower than before. I had planned to buy a new video card anyway but I'm scared to buy a new one and still have problems with the computer. I have tried reformatting etc but it didn't help performance any. It seems to run very slow in games at times, but after a reboot itll run fine for a bit. Youtube videos etc can skip sometimes and the sound will stutter. Even opening folders with lots of files seems a big laggy compared to what I am use to.
Is it just the video card is bad? I thought power supply or ram for a bit but I really don't know.
if u have a second pc then u should swap things around btw the ram, hdd, gpu and psu etc. thats the best and fast way to acknowledge a problem with a specific component. if u dont have another pc then u should probably run diagnostic software for each component.