Hello guys, Here's the prob. When I boot the computer, at the boot screen, it sometimes doesn't show it's 'checking' for the memory(usually it goes from 0 to whatever amount memory I have, 512MB). it skips that step at certain boot ups. When windows is loaded, my DVD drive does not appear(it appears to have problems in device manager), but it did appear to be in the IDE at the boot screen. My soundcard seem to have problem like the DVD drive too. I 'chkdsk' and found some errors, but after correcting, the problem still persists. I did a 'SFC /Scannow' but it failed because my DVD drive can't read my in XP CD. The SMART hard drive info/attributes is all fine. I can't seem to edit the registry although the remote registry is started. Certain programs I installed seemed to not run smoothly. Like my anti-virus prog, it doesn't run it's auto shield. Help me guys, which part of my computer is causing the problem? Thank you.