I'm having a **** problem (or I think it's a problem) with my Windows XP SP3... I start to use Firefox, browse and blah blah blah... and then sometime after it, my pc gets reaaaaaly slow... and the problem is not firefox... when I see the process running in my pc, i see that the svchost.exe is using almost 100% of my cpu! and even after I close firefox, it continues using 100% of the cpu... and i have to kill the process and run firefox again... Why the hell this is happenning?? Will formatting my pc help to solve the problem??

Does the same thing happen when you use IE? If not, then the problem IS Firefox. If it does, then you can blame something else. I'd try another browser to help track down the issue.

I already made the test... it only happens with firefox...

Then Firefox is the issue. Perhaps a plug-in or something is causing it to slow things down... try stripping out plug-ins until it works.

I'll try! thanks! ^^

try going here and get a copy of process explorer
It will help identify what is causing that instance of svchost.
Its a bit like task manager but will identify what created that instance of svchost and what is hooked to it so that you canfix whatever is causing it.
If you are like me there are sometimes 3 or 4 svchosts listed and it is hard to decide what actually turned which one on otherwise.
http://technet.microsoft.com/en-us [...] fault.aspx