sli vga charts: gts 320> gts 640?

What Charts? I don't even see the GST model listed in Tom's charts, just the GTS.

Every article I have seen this discusses this says that the GST is not good for SLI. I could envision the 320mb model have in infitecimal lead when less than 320mb of memory is needed because less memory needs to cycle. In reality, this should always be well under a single frame difference.

Once you go over 320mb, the GST will begin to drop well well behind.
It's not likely you will even need the SLI power when using less then 320mb and hence the SLI will have no point.

Why not get a single 8800gtx instead?

its because the 320mb versions are overclocked

o they are? It makes sense, just thought they'd put "oc" in there with the name in the charts. So I'm an evga loyalist, and if i decided to go with the 320's id get the KO ACS3. Im just hopeing i wont regret going with those instead of GTX in a year, but going sli with the GTX is way expensive.

I'm of the opinion that spending the same amount of money on a single to get almost the same performance as 2 cards is worth it for the ability to buy a second one later.

Another thing to consider is waiting for AMD's R600 cards to come out to compare to and also hopefully trigger some price drops.

thats true but the 8800 gtx slied would bottleneck most cpus so i dont think it would be worth buying 2 8800gtxs if your not running a high resolution

That's why I recommended buying ONE gtx now and buying another one later (i.e. a year or so down the road), when you would probably be upgrading your CPU anyways.