Hello, world! I got an old Athlon 64 PC from one of my cousins, and I've been trying to get it to actually "work". I've gotten the PC to turn on and post once, but now it's being very picky whether it wants to or not. Once i got it to post once, it doesn't wanna turn on. I tried pretty much everything I could, like reseating ram cpu, and taking out ram, etc. I even tried multiple power supplies, and it still doesn't want to budge. The green light is one, so it's getting power, but won't actually power on. The motherboard is an Abit KV-80. I haven't put a heatsink on, so that could be an issue possibly? No, it isn't the power button, because I've tried "jumping" the headers for the power button, and still not powering on. Anything I should try or check?
Here's an image of the whole thing:
Here's an image of the whole thing: