Need a little help here...I always used to seem to correct issues with a fresh install...Tad History: About a month ago my the hd stopped working on my 24" Al iMac...so I bought an external MyBook and reinstalled the OS. No problems until yesterday. The external started making terrible noise and the iMac locked up. So I bought another external, however when restarting the iMac with either a Snow Leopard DVD or a Snow Leopard USB drive, about 50% you can hold the option key to snow those volumes to try and install onto the new external. About 50% of those times there is actually power to the keyboard/mouse so only half the time you can boot off of those sources. When I am able to get them to boot, it takes an awfully long time (like 5-10 min). BTW I did this with/without the new external plugged in so I know it has nothing to do with that. When I did get to the installer I went to Disk Utility and the drive formatted fine...continued the installer...and installed. Upon restart I get a kernel panic which says "unable to find driver for platform" I've reinstalled clean a couple of times, with both DVD and usb drive, same result. Tried reset PRAM, reset RAM...I'm just clueless. It almost seems something is wrong with hardware besides hard drive as you would think that if you replaced hard drive the installed a fresh copy of OS it could be nothing but other hardware. I just thought before I take a few hours out of my day to drive to an Apple Store I would try and ask about it on these forums. I know a lot of you guys are studs with troubleshooting stuff like this. Thanks in advance!