Unfortunately no, it is only crossfire. Nvidia now licenses out SLI functionality but until fairly recently SLI was only available on motherboards built with an Nvidia chipset and your board is a P43 Intel chipset.
I guess if it is really that cheap you can buy it and throw it on Ebay and make some cash. Or better yet, throw both of them on Ebay and they should go for almost enough to buy yourself a better card like the HD5850 or GTX 470.
The HD5850 at stock is about 50% faster than the GTX 260. However what makes the HD5850 so nice is that it can overclock a huge degree often up to 40% which puts its performance in the same area as a stock GTX 480 or about twice as fast as the GTX 260. On top of that it is DX11 compatible and actually uses less power than GTX 260.
That said if your resolution is 1680x1050 or below the GTX 260 should be more than fine for the moment and an upgrade isn't really necessary. It is ok for 1920x1080 as well but the HD5850 would definitely help you max out the more intensive current games.
Okay thanks for the clear explaination! makes a lot of sense this wa
Im playing the games at 1920x1080p all of the time sometimes om my monitor and sometimes on my tv (depends on the mood). still im having no problems boosting Crysis or Crysis Warhead to this res and with high eye candy but its never too early to do some research IMO
situation is as follows about 6 months ago bought a pc with the 260 in it and now i was doing some research if SLi was the way to go in the near future or maybe to make the jump to ATI. (Been looking at the 5870 _sweet card with eyefinity _)
sucks though because my mobo wont support SLi (it does support CrossfireX i believe)
Does it matter that the ATI cards use a 256-bit interface and the GTX uses a 448-bit interface?