For the past few days my dad's computer has been acting very wierd. It started with the system "freezing" frequently, which i believed was something wrong with drives, fixed drives through using "verifier" but afterwards the computer has been incredibly slow and when opening task manager the CPU is at atleast 90% but mostly 100% when no programs is running. The computer is just turned on. The computer works just fine in "safe mode" so it can't be the CPU giving up, but what can be done to get the CPU working like normal again? Feels like i've tried everything now and the XP "bible" is no help at this time.
Help :S

Go into task manager, click the "processes" tab and find out whats draining your CPU.

P4 3.20HT 800mhz FSB
Abit IS7-E2
2x1024mb OCZ Value DDR400 Dual Channel
80GB Diamondmax9+ SATA 160GB Diamondmax10 SATA Sapphire Radeon X1650 PRO 256mb
Hiper Type R 530W PSU

The "verifier" that you mentioned is probably the "driver verifier". It's used to troubleshoot driver issues, not problems with the hard drive(s).

Most likely, the PC is infected...either a virus, trojan, hijacker, or spyware. The fact that "computer works just fine in "safe mode"" pretty much confirms that whatever the problem is, it's loading at startup. It's not a hardware problem...it's a software problem.

Start by checking the processes in Task Manager as was suggested by Pariah. Run MSCONFIG from Start > Run, then click the Startup tab to see if anything suspicious is listed there.

http://www.netsquirrel.com/msconfig...

Do a full antivirus scan, scan for spyware. Download/install CCleaner & use it regularly.

http://www.filehippo.com/

It's "SYSTEM" that eats all CPU mainly. I have done a full anti virus and spyware scan, but problem remains. There's no virus in the computer.

is it svchost.exe service that takes so much cpu?