Okay so this is my dad's old computer, old is a relative term. A lot of the components just got replaces and upgraded before it came to me. Well the computer was working fine and then I turned it off yesterday and a couple hours later turned the computer on. It beeped a couple times, and it booted up to a messages saying CPU fan error press f1 to continue. I press f1 it boots up like normal but keeps freezing for around 30 seconds at a time. I look and the cpu fan will spin for maybe a second, then stopped repeatedly. I've cleaned the cpu fan and heatsink. I unplugged the fan. I honestly don't know what to do. I have another cpu heatsink from my old computer and I'm thinking I can just swap it out. But I don't know what makes heatsinks interchangeable. Unfortunately the fans are not the same size. But the bases that would go on the thermal compound and cpu are near the same.