I've got a 7800 in my case and I have so many heat problems that I have to run it with the top of the case off. Just make sure you've got a good cooling solution.
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Brent
RioCar MK][a 20GB+80GB
'96 Saab 900s (Not any more)
Still looking for a good way to install in a 2010 BMW 3 series with iDrive/NAV