Originally Posted by Fotis
When Nvidia does not warranty overvolting its cards I fail to see the problem.
You are correct.
The SWEClocker guys/others hacked the registry to allow higher overvoltage than would have been allowed by the cards, and did not use anything to compensate for higher temps like water cooling.
Then they post videos "Look- we're the world's worst OCers and managed to blow up this card!"
newegg sells 8 brands of 6990s, and you can buy seven of them right now if you like- all of the brands that will not warrant the overvoltage OC flipping the AUSUM switch provides. So basically XFX is figuring they'll take the higher sales and hope returns of burned cards won't exceed profits.
7/8 ATi vendors won't warranty you overvolting their card either, mainly because it damages cards.