I have an out-of-warranty 1.8GHz 20-inch iMac. The slot-loading SuperDrive just developed the problem that it doesn't pull in the disc, as if it doesn't know you inserted one. There isn't already a disc in there. Following Apple's do-it-yourself diagnostics from their iMac G5 support page, I found that the Mac can't see the drive at all, as shown in System Profiler. They recommend this procedure to re-seat the drive and, if that doesn't work, replacing the SuperDrive. I'll be careful to be electrically grounded, protect the screen while the iMac is tipped over, and all the usual precautions. Have any of you had this particular problem? Have you done this procedure? Did it correct the problem? Thanks!