IDEA Using 100% Of CPU

I just started working at a new office and downloaded an installed IDEA 3.0.4 onto my Win2000 PC. However, whenever I run IDEA and I look at the Windows Task Manager, the CPU Usage is 100%. Even if IDEA is just sitting there, open, doing nothing. And even if IDEA is the only open application I have. If I shut down IDEA, then the CPU Usage goes back down to something reasonable, like 5%.

Can anyone explain why this is happening? I've been using IDEA for over a year and have never had this problem.

Aidan