I posted about this a while ago, but it hasn't been solved, and lately a few different things have happened.
Whenever I load something and am listening to music, the music stutters. Also, my mouse pointer will become chunky as I move it, and whatever programs I'm running also seem to take a performance hit. My CPU usage jumps up to 100%.
Before I installed a 250GB hard drive in addition to the 150 GB that I'm using now, I didn't have any of these problems. I've tried disconnecting the 250, but that didn't work, so I set the 250 as the master, disconnected the 150, and tried installing XP on the 250. However, I still was getting the same problems. I've replaced my motherboard, because I thought that was the problem. I ran a memory test to test my RAM, and that looked fine too.
Just a few minutes ago, I was playing a game and my computer crashed to a BSOD. I didn't have time to write down what it said, though.
Whenever I'm playing a game, the hard drive makes some strange noises. This doesn't happen consistently, but every few minutes it will make the noise (almost sounding like it's starting up then stopping again or something). This also seems to be around when I the game freezes (sometimes for about 90 seconds straight).
The only thing I can think of is that it's a power issue, but even when I disconnect my video card and second hard drive, it doesn't seem to help at all. Maybe my PSU has just gone bad at this point?
My computer idles at around 32C, and while playing a game it never seems to rise above 42C.
I tried running off Knoppix (live cd) and I didn't notice any lag running it. Maybe that's because I wasn't able to do anything CPU intensive, though.