Meh, its all weird, there will be someone who wins at stock, and I'd be surprised if that wasn't AMD assuming both cards are aimed at 375W for "stock", and a card that wins at max clocks.
The 590gtx should win at max clocks, but that also assumes that it can pull, and cool, enough to blow past the 6990 as 580gtx sli would. THe problem being, that will be two VERY high power gpu's on one card, probably better cooling than AMD's so I wouldn't be surprised if it was cooling and probably quieter at the same power levels, but watt for watt AMD has the advantage, can the card actually draw enough juice to hit the clock speeds it needs, we'll see I guess.
The other little issue is benchmarking the 6990, too many people just hit the oc bios saw high temps in furmark and that was it, the problem being 6990 max clocks and performance in games will be significantly higher than max clocks in furmark, the OC bios gives some silly "powertune" setting but the clock speeds aren't using that power up at all, only in Furmark.
What we'll need is a reviewer with half a brain(are there any left?) who will actually find the stable maximum overclocks on both cards and see who wins.
Anyone that buys either of these cards(or a 5970) and runs at stock speeds needs to be slapped frankly, stock speeds = daft pci-e spec limits, nothing more or less, overclocked = where a £450-700 card should be used.
EDIT:- Seriously, why on earth have AMD made a card with plenty of space around the fan in the middle, yet, made the fan much smaller than the width of the card. Nvidia have a much larger hole in the shroud and have fitted a much bigger fan, it seems utterly utterly retarded to not have sourced a bigger radial fan if they absolutely had to go that way, as I'm sure a bigger radial fan could provide less noise for any given airflow, but radial fans are just rubbish, always.
