When I defrag or run a virus scan, I get the blue screen with a code of 0x000000f4. Asus K8V-X motherboard Athlon64 3400+ Western Digital 120gig sata hard drive - setup using OS scsi drive software Windows XP Pro OEM, service pak 2 2.5 gig of DDR1 ram Ram is ok. Something is causing my Windows Xp to stop responding. I'm noticing that majority of the people with this problem are using Asus motherboards and Athlon processors. I don't know. PLease help!!!!!!