Win each 30s increases performance on 100%

I have new Windows (install maybe 2 days before). After install Awast home my windows XP sP2 always each 30s increases performance rating in CPU. normal rating is 2%-5% always, but i start awast CPU each 30s increases and my work in PC is very sllllooow. i must wait after CPU get 2% performance. This problem must be with resident protect, now i have turn off this shield and work is normal all day 2% CPU performance. But after start resident protect- (instant messaging,internet mail,outlook/exchange, P2P shield,network shield,standart shield and web shield), my CPU each 30s increases performance on 100%. Please help me…

Update- problem is only with P2P shield … this shield i turn off and after CPU working normal

What P2P program are you using? There were some problems with Bittorrent clients…

Yes i use - uTorrent programs - this program is P2P network…

JJ používám uTorrent, ale tam nic takového není na nastavéní - pouze jak se připojit atd…ale v antivirem nic …

Can you check if the CPU performance peak is due to ashServ.exe?
If you have the residents settings window opened, will you see which is the file that is being ‘scanned’ and then ‘using’ the CPU (Last scanned file)? If you search the board won’t you find the specific solution for that?

Please see:

http://forum.avast.com/index.php?topic=28467.0