I bought six of these cards, two of them have already gone. What I noticed is that they sparked near the PCI-Power connector after I found my system randomly shut down. I think some of these are definitely defective, these were the batch from early January. I feel like it could be the power supply I used so I am trying with different power supplies and seeing if anything happens.
Thats exactly what happened to my Sapphire 7950s. 2 out of 4 were fried this way within one month. Beware they were undervolted to 1.036, running below 60C and powered by a Corsair Platinum PSU.
Still waiting for a replacement.... I am done with Sapphire for sure