This 2008 iMac has been trouble. In the past it's needed a new GPU ($400 later), with Apple Care saying it was the logic board, and a privately owned certified shop saying it was the GPU. I opted in for the GPU repair (the iMac was still booting, but once the GPU diode temperature reached 55c, on screen graphics would fail), which fixed everything fine until now (6 months). As of now it fails to start, freezing at the Apple logo and spinning loading symbol. Resetting SMC Control has not helped. Resetting PRAM has not helped. It fails to start from the Install CD, again freezing at the Apple logo (albeit, I'm using the install CD from a different model, but same OSX snowleopard version). It will not start in safe mode. This all leads me to believe there is a hardware fault (HDD I hope) or permission issue. Yet... it starts up in Windows XP Bootcamp without problem. I ran the Hardware test. It came up with the following error code: 4M0T/1/40000002: 0DD-0 From the googling I did, this error code is consistent with either a fan-control fault involved with the optical disc drive or HDD, or a logic board fault, with no one apparently knowing what the 0DD-0 exactly means. Okay, logic board fault, I can accept that. Except that Windows XP still works fine. I've yet to try to firewire anything yet – I don't have the firewire cable. What's your speculation on the issue? edit: Tried to boot an OSX install from a USB HDD. Kernal panic. edit2: DxDiag in Windows XP isn't detecting any display devices or drivers. This is after doing a clean current driver upgrade. Any 3D programs state a DirectX error, even after verifying directX. Any thoughts?