I am having problems with my iMac G5 (which I have named Karen). It has suffered irrepairable file system damage to the internal hard drive twice in the last 5 days. Restoring from a recent backup made it run for a while. It is running the second restore as I type this (or at least it should be). I've also experienced a kernel panic while trying to restore from backup. This rendered the internal HD unreadable, and required me to erase it again. The first filesystem error was an invalid sibling link, and the second an invalid node structure. Both times, the underlying task reported failure on exit, according to Disk Utility. After the kernel panic, I got the flashing Mac folder icon with a question mark briefly before it found the backup drive and booted from it. Also different from before is the fact that, when the Mac boots, the fans kick up to full speed for a while, then back to low. It takes longer than normal to boot, and sometimes refuses to boot altogether (just sits at the gray spinner screen). Anyone have any ideas as to what's up? I am planning on taking it into my local Apple Retail Store to have it looked at if the cause isn't something I can fix.