Well you have to take into consideration various things for starter the 8800GT is very close in performance to a GTX logically two of them are faster as shown in various Performance Preview that have been already out since the launch of the 8800GT, and second and most important Driver optimization if they can't or don't optimize the driver for SLi performance there will be no point in trying to get SLi or CrossFire.
Dude I honestly don't care much about SLi even less for "CrossFire x4" so I really can't tell how 4 video card will work, I know that SLi use 1 card for half screen and the second one for the other half if I'm correct but let me ask you something do you really would buy 4 High end or even mainstream video cards??
Well if AMD/ATI's CrossFire can guarantee me that all current and most 1 to 2 years future games will run with high resolutions and all setting maxed with more than 100FPS (steady) it would be a serious matter to think for enthusiast that can spend all that money and want the best performance for their "high end PC". Do you honestly would buy that "CrossFire x4" to get 10 FPS more ahead of a single video card solution?
Anyway well have to wait & see, in the mean time I'm going to do a little research
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