I have found a listing on Ebay for an iMac 17" Core Duo (http://www.everymac.com/systems/apple/imac/specs/imac_cd_1.83_17.html) "The computer turns on but a file with a flashing question mark comes up. I've looked online and they say its either a faulty motherboard or needs to be rebooted" This is what the listing states. I know that the flashing question mark means that the computer cannot find a valid operating system, however the listing says that it could be a faulty motherboard. Is it true that it could be a motherboard, the list is pretty cheap for this reason and I could easily reinstall and operating system, but I don't want to go through replacing the MLB. Is there any chance that it is anything more than the hard drive/hard drive cable?