Vaderpro... you gotta choose your benchmarks better. Doom 3 is nividia optimized, which means obviously all nvidia based vidcards will tend to do better since that game's biased. Mainly in their choice of shader calculation system apparently. So yes, if I were to throw an HL2 benchmark at ya, the ati cards would come ontop.
Now, UT2k4 is somewhat nvidia optimized since they have the nivida logo on the intro, but look at the results:
as you can see, 6600gt series tends to outdo the x700 series. But only by a mere 7F/S. Not very much. So yeah, cheaper, but tends to run better on ut2k4. Nowadays, you should try n' get your vidcard around the games you play the most really. If you find yourself playing the source engine (HL2, CSS) games more than UT2k4, COD, D3, and other nvidia-optimized games, then sure, get an ATI, but if vice versa, then get nvidia... rediculous how this is now where optimizing games for companies matters more than their brute preformance.....
I won't bother with the 3DMark scores, both ati and nvidia have been caught cheating on this one several times over.
Ok, so here's the most even benchmark on tom's hardware, far cry. It's a neutral game. This is one you should measure the brute preformance by, and it does seem to read out how one should expect the cards to go:
the 6800 SLI's ontop, follow by ati's x850 XT PE. Now, this benchmark proves why I think SLI's a waste of cash for now. Paying rediculous amounts of cash for 2 vidcards, while 1 vidcard is barely trailing behind... yeah. The price/preformance ratio is definately on ati for the higher end vidcard solutions for now. Heck, check this out:
6800 U SLI: 135.2 F/S
6800 U: 102.9 F/S
That gap, for literally doubling the pricetag? They better throw in lifetime warranty, but they don't. So not worth it. Ok, so maybe games as of right now do not take full advantage of SLI.. but in the near future, do you think every game will support it? How bout 3DFX back in the day? how many games supported that?? like 5? yeah, great. I think just by luck, G.O.D. felt pitty on the people with old voodoo 2's and supported it in the Serious Sam series, maybe just for kicks, I dunno.
This's just what I think though people, it's up to you guys to decide if you think SLI will go the full distance or not... sweet jebus I went offtopic diddn't I? may the fourm admins be kind to this poor soul.
To try n' bump myself ontopic.. I say go for the 6600gt. ATI's been doing only a decent job on their PCI-e lineup, but Nvidia's been working overtime to ensure they came out with better, and they did. This definately makes up for their Geforce4 lineup. Same goes for most of the FX lineup too. It's kindof like ati n' nvidia's reversed themselves eh? on that final agp strech, ati was ontop with the 9800 pro, great card, great price. Now it's nvidia with the great card n' great price (the 6600GT). Interesting how the computer world is like, "give-or-take".. or at least I think so cause I'mma odd computer geek.