I haven't read all the reviews but this caught my attention. Taken from the techpowerup review.
As a first step, I increased the voltage from 0.938 V default to 1.000 V, maximum stable clock was 815 MHz - faster than GTX 580! Moving on, I tried 1.2 V to see how much could be gained here, at default clocks and with NVIDIA's power limiter enabled. I went to heat up the card and then *boom*, a sound like popcorn cracking, the system turned off and a burnt electronics smell started to fill up the room. Card dead! Even with NVIDIA power limiter enabled. Now the pretty looking, backlit GeForce logo was blinking helplessly and the fan did not spin, both indicate an error with the card's 12V supply.
After talking to several other reviewers, this does not seem to be an isolated case, and many of them have killed their cards with similar testing, which is far from being an extreme test.
Hopefully this isn't a widespread defect in the first batch shipped.