My PC is a custom built rig that I got for Christmas of '07. Everything was working. A couple of months ago, I noticed my processor fan isn't working. I took nothing of it and here I am getting worried. Everything's hooked up right, the fan does spin when I spin it. It works when the computer is off for like 1hr, and then I turn the computer on, that is when it works and it continues to work until I turn it off again. The only reason I care is because I bought Portal, and that is taking 100% of my CPU power. (2.2Ghz Core 2 Duo E4500). It runs for like 2 minutes, and then my computer turns off because (I'm guessing here) my processor is getting to hot. Anything I can do or something?