I have the GTX 590 (not the 680)... and i love it.  It does have a few "issues" - none I can pinpoint right off-hand... other than it took a few tries before I found the "right" driver version that made Vue happy.

Could be some other things that occur on this system that MIGHT be video card related, but might NOT be... like my flash drivers "freezing" now and then (causing me to have to completely reboot...), and a few other lil odds and ends - but nothing that I really freak out about anymore LOL.

Yes, you DO need a good sized power supply for these cards... 550 is MINIMUM - consider going higher... SERIOUSLY consider going higher power.  The card will suck that power supply like no tomorrow and beg for more - specially - and mostly - when Vue is rendering.  Take into cosideration what all will be drawing power from that supply... and plan accordingly. =D

Let us know if you go with the 680 and how it works for you! =D

Rarer than a hairy egg and madder than a box of frogs....

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