So I have a 2008 Macbook Pro with the nVidia 8600GT that won't boot at all - no chime, no noise out the speakers, no display. I've sent it in twice to the Apple service agents in South Africa (Core, unfortunately not the most trustworthy company) and they have twice offered me a quote of $900 for a Logic Board replacement as my only option. Before the second return, I spoke to Apple in the UK and got them to create a case number that Core could look up. The Apple agent I first spoke to said it sounded like it was the 8600GT problem, and that he would make a note here that they must specifically investigate that. Unfortunately, Apple has a test that Core runs from an external HDD, and they feel that if that test passes or cannot run, then the problem is not the 8600GT but something else. Now, from my understanding of the problem (solder joints below the graphics card failing over time due to heat cycling), Apple's argument that the only result of an 8600GT failure is a black screen but a computer that still powers on is illogical and flawed. Surely if random connections to the GPU are being severed, that could result in the system not switching on at all? I've seen on the forums that some people with the same problem as me (computer not booting far enough to run the test) were still able to get Apple to swap out their logic board. Has anyone got any advice on how I can proceed in this? Surely it's Apple's responsibility to prove that the system does not have the nVidia fault, rather than my responsibility to prove that it does? Otherwise, how much does a Logic Board replacement cost in the USA? I think the $900 they want to charge me in SA is ludicrous. I've read on older threads of people being charged a flat rate of $330 for a logic board replacement - is this still the case, or have the prices gone up? Finally, does anyone know how I can investigate further if this Macbook Pro does or does not have the 8600GT problem? Would there be any physical evidence, or any information (error logs etc) I could take off of the drive?