After about 10 minutes, any game I launch in Big Picture mode crashes "Big Picture Fatal Error Device was removed. This problem is usually caused by bad hardware or drivers" (it says something along those lines).
I used DDU to wipe out all drivers and then reinstalled the 15.15.1004 drivers - same issue. I exchanged the card for another one - same issue. I reformatted my computer and installed the latest 15.7 drivers - again, same issue with Big Picture mode crashing. It does not crash on my GTX 460.
Anyone know what might be going on or how to resolve this issue?