I have a server with a 3Ware Escalade 8506-8 S-ATA RAID card in it, running Windows XP Professional. Today I thought, "Well, I might as well upgrade to SP2. It's been working just fine on my other machines!" Bad idea. Machine no boot now.
Looks like I may have to reinstall. Luckily, the system itself is installed on a standard ATA IDE drive, so it's not as complicated as it could have been. I only regret not imaging the partition before attempting the service pack patch. Stupid me! Argh.
Update: A fresh install from a SP2-slipstreamed XP Professional CD does not solve the problem. Upon reinstallation and reboot, the system hangs at the XP logo screen.
Update: I'm back up and running (hours later). Solution was to reinstall XP and apply the XP SP1a update (reinstalling all drivers, including the 3Ware Escalade driver).