Hi! My 8800GT started generating some modern art, so it was time to retire it. I read on this forum that, while not officially supported, the HD6870 works out of the box on OS X, that one of you fine gentlemen made drivers available, and that it obviously works normally in Windows, so I purchased this card, along with a pair of 6 pin power cables plugging into the motherboard. I tried to install it, and my problem is as stated in the title: the fan spins loudly, but the card is not detected at all, either by OS X or Windows 7. Screenshots of osx hardware profiler and win7 hardware manager attached to this post. So, now, the obvious next step is to try this card in another computer, right? If I could do that life would be grand. But because [life story here], I'm currently stuck in this small village where I don't know anybody, so that might take a long while. Until I can do this, could you think of some more diagnoses I could do to figure out if my card is busted, or any idea if I did something stupid? Here's what I tried already: * Tried both 16x PCI-e slots (slot 1 and slot 2). Both work with my HD2600 so I know the slots are not faulty. * Tried to plug a monitor in the 6870 in both HDMI and DVIs. * Tried to boot with only the 6870 (nothing happened) * Didn't try to use the the provided power cables that plug into the horizontal 4 pin connectors (forgot what they're called) that are used for optical drives. Should I try them? It'd be a bit cumbersome to do it since I need one of them to power my SSD ghetto mounted in my optical drive area, and that SSD contains my OSX install. I am currently using a pair of 6 pin connectors that plug into the motherboard, similar to the one provided with the official 8800GT. Thanks!