Those temps sound REALLY HOT! I know you're in Jeb Bushlandia, but still 62C is on the high end. My Athlon 2500 Barton Core never breaks 39C at room temps of about 20C. Realize that I'm in Wisconsin however, and it's winter here now
! I also have a Vantec Aeroflow cooler on my processor and that is possibly the main reason of the low temps for my processor, but also the Barton core has lower thermal dissipation (smaller conducting pathways, I think). Even when I load my computer with hefty Fortran codes doing big iterative matrix solves or I'm fragging pixels in UT2003 I have yet to get over the 40C mark! Good case cooling is just as important as well! Try to get those temperatures down somehow, switch to a Barton core if your's is not already.
Other relevant questions:
=> What distro of Linux are you running?
=> Did you
compile the kernel?
=> Do you have AGP "Fast Writes" or "SideBand Addressing" enabled?
=> Do you have "good" memory (Crucial, Corsair, or OCZ)
=> Do you have sufficient power supply (300W to 400W)
Diagnosing your problem is quite difficult from knowing only a single symptom.
I'd recommend starting with doing a power balance analysis. Estimate how much power your hard drives, graphics card, and processor eat up, then compare with the power rating of your power supply. Usually system weirdness can be attributable to power supply issues, but that's only a hunch.
Hope this helps!