I'll spare you the gory details, other than to say I just upgraded my MoBo and CPU. My boot drive was XP-Pro on two 500GB SATA-II drives in a RAID-0. I also have one IDE drive with the Windows7 beta on it. After swapping out my dead MoBo for the new one, XP would spontaneously reboot as soon as the loading screen appeared. So I rebooted into my Win7 installation on IDE-0, which reconfigured itself for the new board, and after loading the Raid driver off the MoBo CD, even detected my Raid-0 and gave me access to all my files! After slipstreaming the new MoBo's Raid drivers to a new XP cd (I have no floppy), I was able to run the XP Install CD hoping it would detect and Repair my XP installation. No such luck. I rebooted the CD and went into the Recovery Console. It detected both Windows installations (XP & Win7). I chose XP, verified it could read my files with DIR, then tried a Chkdsk which reported the following error at the 75% mark: 'The volume appears to contain one or more unrecoverable problems' So I went back into Win7 and rechecked my Raid drive from there. It scanned the drive(s) and reported no errors (actually, Win7 reported nothing at all, the window just closed when it finished). Just in case Win7 had fixed whatever was wrong, I rebooted the XP cd, did another Chkdsk, and got the same result. The files on the disk(s) appear to be fine. A friend tells me it has something to do with the "Hardware Abstraction Layer" and XP not recognizing the old installation's raid format since it was formatted using a different controller (a Silicon Image 3114 raid controller on the old board, which is not on the new one). It seems like this should be easily fixable. There's nothing "wrong" with the drive or data itself. XP just doesn't like the chip it was formatted with??? Does anyone have an idea other than "back up one Terabyte of data to a drive I don't have, reformat, copy everything back, and then spend the next week reinstalling and reconfiguring all of my software & Windows settings", please? TIA.