What kind of monitor do you have and at which resolution do you intend to play at ?
Unless you got a high end monitor that can display more than UXGA (above 1600x1200), SLI'ing a pair of 7900GS is just money down the drain as you won't see a worthwhile improvement over a single GPU solution at "lower" resolutions. On top of that, games that are not optimized to take advantage of SLI will only use a single GPU out of the two, the other will just sit idle, again, money down the drain.
Thanks for the info SidVicious, i am using a 17" LG, at a "lower" res, what i will do is go for the card, but only get one, that way i have the chance to upgrade latter down the road.
Seriously. You are running a 17" monitor and want to do SLI???
Fyi, I have a Dell 2407fpw, run it at 1920x1200 with all effects enabled except very high anti-aliasing, and find that a SINGLE Ati x1900xt is adequate. Worst frame rates in FEAR were around 30fps. Getting two cards would be nice in my situation but not necessary. Better to avoid the potential problems with SLI or Crossfire, and also to wait for the DX10 cards before committing a lot of money to the graphics.
If a single card can drive games at 1920x1200, why would you need SLI for gaming at something like 1024x768?
Damn right. An E6300 and a 7900GS should be good for gaming with your monitor. My older pc has Pentium D 820 2.8Ghz and a 7800GT, 1280x1024 resolution and high quality on BF2 and still manages 60-80fps on single player mode. So with that an E6300/7900GS rig should run any game today with good quality and performance.