It's running in an un-airconditioned garage that hovers around 95f, hottest card gets to 78c
95 is pretty damned hot. I am lucky that I live in a house with a deep stone-wall basement. Perfect for chilling wine (if I could afford some) or housing noisy computer equipment. Even in summer it's maybe 70 degrees down there.
But seriously man - you want to put that nice rig into that hot ass garage? I would be digging a hole or finding somewhere else I could hide that. Even if it was at work, or at a friends house (who you would have to pay for power I am sure). :-)