What overvolting are you talking about exactly? Each time you post, you throw that word around. I don't see ANY overvolting. All I see is a switch that increases performance on a card by raising clock frequencies with a small voltage tweak that is WITHIN SPEC OF THE CARD. The reason it's not warrantied by 7 of the 8 manufacturers is because flipping that switch takes the card out of PCIe power spec. Allowing users to do such a thing would not only increase power draw to a level that's not acceptable for everyone to use (see 750-watt power supply...), but it also causes the card to become noticeably more noisy. That, by itself, would result in RMA's and loss of business. XFX is taking a risk, but it will more than likely pay off in the long run. Retain your customer base, and you will likely profit from it.
Guaranteed that AMD put that switch on to give users extra oomph, not to make the card unstable to the point that it will croak. If that was the case, AMD would not have done that. These are handpicked chips that are the best of the best in Cayman XT form.
Notice how Nvidia doesn't have a switch like that. AMD did this to make sure that their card is the fastest, regardless of what Nvidia chucks out. Mission accomplished. Notice how Nvidia's card is a lot smaller. I have a theory on that one; less power regulation circuitry, thus resulting in little puffs of smoke. AMD got this one right. Nvidia cut corners, and is paying for it now.
Honestly, do you have nothing better to do than to defend Nvidia? Think logically for once, please. No manufacturer in their right mind would put out a piece of hardware that could be clocked out of spec simply by flipping a switch. The thought of such a thing is absurd.
The overclock itself amounts to a fairly minor GPU core frequency increase of 50MHz, along with an extra 0.055V added to the vcore of each GPU.
Do you honestly believe that that few extra hundredths of a volt will cause the card to croak? You're mad if you believe that.