Unless you're getting each 8800 GTS 320 for like 50 bucks, not worth it at all. The shared 320MB of memory is not enough for max resolutions with any filtering in about any modern game, it's old G80, and I think a single 8800 GTS 512 would beat out the SLIed 320 GTS.
Wait for the new cards, or if you really can't the 9800 GTX would be a much much better purchase. 2 mid-range cards in SLI will not beat a high-end card.
If you already own two 8800GTS 320MB now, don't buy an 8800GTX or 9800GTX. Your two cards would trade blows with them. Often they could easily beat an 8800GTX or 9800GTX by a good margin. But the Problem is though your 320MB memory, so higher res with fsaa where SLI often crush a single GPU (an make a playable difference) you will be memory limited instead.
As an example of how 320MB GTS SLI can beat an 8800GTX look at this old review (= old games ) ...
Yeah, I wouldn't doubt 8800GTX > SLI 320MB GTS in Crysis but I have not seen any benchies of those games showing if the 8800GTX can beat them or not.
Considering how bad a single 320MB GTS does in crysis, I can imagine two in SLI would also drop off bad as resolution goes up. Problem is, a single 8800GTX doesn't do all too well in Crysis high res high detail either, and forget fsaa. So the SLI 320MB GTS may lead medium details and high details at lower res. At some point in high details the 8800GTX would pull ahead, but would it be at a playable resolution or would it be a 24fps vs 19fps victory? Basically at max playable settings with a single 8800GTX, (16x10 mostly high no aa for example), would the SLI 320MB GTS be behind? Anyway, like I said I ahve not seen it tested so this is guesswork. I would like to see it done, especially actual gameplay not the GPU benchie most sites use.
For those reasons, I decided way back not to buy a second 320MB GTS but instead buy the two 8800GT 512MB. But I just bought the $88 shipped no rebate Zotac that is in-route, so I'll soon get to test (cheaply!!!!) SLI 8800GTS 320MB.
Still for the OP who already owns two 320MB GTS, I would never recommend an 8800GTX, Ultra, or single G92. SLi 8800GTS 512MB or the next generation cards (GT200) would be an actual upgrade.
I'd think in games a single GTX can handle 19x12 with fsaa, then yeah that would probably put a hurting on the 320MB. Crysis though SLI 8800GTX can't even handle those settings.
I'd like to see 8800GS 384MB SLI vs 8800Ultra and 9800GTX. The things are ridiculously cheap at $99 shipped AR. I'm going to test 8800GS SLI vs 8800GT SLI, but unfortunately don't have access to any of the big boy GPU's (GTX's and Ultra).
You sure have the time to test but i cant because i have to study and studying in IRAN is probably the hardest u have to read 33 books in 9 months and then u will have to pass a 4 hour exam
Also i say that 2 8800GTX in SLI can run Crysis @ 1920x1200 with very high quality but i think with 0xAA right?
Because i was just looking @ the benchmarks of DUAL 8800MGTX (8800MGTX performs a little lower than desktop 8800GTX) and it could run Crysis @ 1920x1200 with very high quality with 0xAA:
As u see with VISTA ULTIMATE it got 18.4 for Min FPS, 41.4 for Max FPS and 34.7 for Average which is pretty good but yeah this is without AA
AA kills the performance also it isnt very much needed for high resolutions like this, because when i tested my 8800GTX with 1680x1050 with 0xAA and 16xAA i didnt see a noticeable differences, i think AA is more useful in lower resolutions