Yest i left my computer in the logon screen for 1 hr when i came back there was constant hard disk read... i tried working in the sys but the sys was slower than usual and sound was cracking.... there was a lot of hard disk read than usual... checked for spyware n virus.. the system is clean... some 2 months ago when i had the same problem.. i just exchanged the IDE port in the mobo for HDD and DVD writer and the problem was solved... so tried the same now but the system was even more slower when it was restarted... so restarted again but the OS wudnt boot... said some file is corrupt... after that it did not start at all... it said that boot records wasnt found and wud stop.... tried exchanging the IDE cable but no use... I suspect its the problem with the IDE port in the mobo... how do i trouble shoot this problem? any ideas? anyone faced similar probs like this? my sys config is AMD Athlon 2600+ MSI KT4AV mobo MSI GF4 Ti4400 512 MB Hynix Seagate 200GB HDD Philips PBDV1640P DVD writer.