I have been eager to try the new SLI setup. My mobo supports it and my old card is crap. (HIS Radeon 1650 512ddr2).
So should I go for an extra 50 bucks and go 8800? Help!

In a word - yes.

A single 8800 GTS 320mb will kick the living crap out of two 8600 GTS, not to mention GTs...

On games were SLI works...

2x 8600gts are on par with the 8800gts 320mb

On the games where SLI does not work the 8800gts is about 90% better than the 8600's

I would get the 8800gts and then down the road if you need more hp SLI that...

8800GTS without question.

w/out thinking, 8800gts

Found some benches. Jwolf is right:

http://www.tweaktown.com/articles/ [...] index.html

However, since two 8600 GTS's would cost more than a single 8800 GTS, I assume the OP was considering 8600 GT's... and a single 8800 GTS would kick a pair of those out of the park everytime.

I'm pretty sure we already decided on this like a dozen posts ago. Just think about it... the 8600 GT has 32 whatevers... and the 8800 GTS has 92 whatevers (128 if you go the GTX/Ultra route) ... so even if the 8600 SLI setup is 100% efficient (meaning you actually double your performance) then 64 is still less than 96.

So easy a caveman could do it.

8800GTS hands down

And then of course there are memory considerations. Speed and bandwidth which the 8800GTS also has more of unless you get a completely pointless 512MB 8600GT.

-mcg

Obviously it's a no contest, the difference between single 8800GTS and SLI 8600GTS is still abysmal to say the least.

Just to clarify... if a game box recommends a 512 MB video card, it does NOT mean two 256 MB cards SLI'd... a game like that would absolutely hammer that sort of SLI setup.

I imagine once the 8700 series is released we'll have a whole new round of SLI vs. single card topics to discuss... and although that one should be a bit closer, I'm going to make a pre-emptive SHHH!!! and say that the single 8700 is the winner over an 8600 SLI setup.

Rodney's right, actually.

Two SLId 256mb cards are both using 256mb of texture memory each, and the texture data is duplicated for4 each card.

Therefore they can use a texture memory set made for 256mb, not a 512mb texture set.

No, I'm saying SLI'd 256mb 7600 GTs can only use up to a 256mb texture set without a massive performance penalty, but a 512mb 7600 GT can use a 512mb texture set without a performance penalty.

That's texture resolution though. Assuming they're both using a 256mb texture set, of course SLI'd cards would be faster.

If they were using a 512mb texture set, it's hard to say if the SLI'd cards extra GPU would benefit over the single card's extra memory.

What cleeve is saying is, "You can't drop a 512 lb rock into two buckets that support 256 lbs each. You have to have a 512 lb bucket to be able to carry that rock. And 'no', you can't break the rock."

And SLI / Crossfire is not a joke, it is a premium service to increase performance. It is not meant as a method to save money, but a way to increase performance at diminishing returns. Some people need and can afford the extra performance, so the option is there.