100% CPU Usage

I exit out every program I could find in Task Manager and I still see it using 100% CPU usage. I did a clean install and yea that fixed it but how would I fix it otherwise? My girlfriend's laptop has the same problem and it abruptly shuts off because I guess it is overheating. Any ideas? I'm thinking possible virus but anything would help. Thanks guys.

select the processes tab and click the CPU column to see what is the 100% offender..

Fixed. Lol 4 viruses. O well it's fixed.

Wait it's not fixed. Now it's back up to 100%. Scanned again and no viruses. I checked the processes tab and no 100% offender is showing up. Anything else I can do?

ttt for answer

run adaware and spybot, you probably have spyware running silently in your processes

Like bob said, in the processes tab, it lists which programs are using the processor. The program might not be using 100%, but it'll give you a good idea what to check.

quite a few virus/malware bugs will hide themselves on the process list. Pain in the ass, those ones.

My sisters laptop has a similar thing going on. Not only 100% CPU but it's stealing some serious bandwidth as well. Notice one of them was called CYGCFG32.exe and some other were named to look like windows apps (SVZhost.exe f.x.). Did the online virus scan thing (my sis doesn't hvae a virus scanner), it did find 8 viruses but it's still bad (albeit not AS bad). I googled cygcfg32.exe and read that someone had a similar problem that was fixed by deleting cygcfg32.exe which i did, but i have a feeling it's got a lot more programs then just that one running.