The thread title pretty much says it all. Before 10.6.3, I had 2 x 500gb internal sata drives set up in a software raid0 configuration, working great. After the update, only one of the two drives shows, while the other says "missing/damaged" in both disk utility and terminal "diskutil checkraid". I'd hate to lose the near-terabyte of information, so before I say it's dust, I'd love some input. Something else that I find interesting is that the "Serial-ATA" tab in the System Profiler.app says this "There was an error while scanning for Serial-ATA devices." whereas before it simply listed all four of my internal drives. I'm running a Mac Pro quad core, with a modified ATI 4890 HD 1gb video card, but that's working fine thanks to Cindori and Netkas's update. Also, in Disk Utility, the "missing/damaged" disk is showing up as "Media" in disk utility, listed where it should be in Bay 4, with no mount node, no SMART status, etc... Sort of just a shell drive or something. Does anyone have any ideas as to how to re-convince OS X that the drive is actually part of a raid slice? And/or how to get my Serial-ATA section of System Profiler.app to work correctly again? So far I've reset PRAM, reset the SMC, and repaired disk permissions with disk utility. Thanks in advance.