98000gt SLI vs HD4870

Normally, Not always, SLI performance depends on a games ability to scale, ing ames like Lord of The Rings Online the 4870 will be 40%+ faster that the 9800gt sli setup. SLI introduces new problems of its own, micro stuttering and odd issues with scaling at certain resolutions, sometimes even causing a reduction in frame rates over a single card.

In games where it works well it will beat the 4870, but at the moment SLI and crossfire are both inconsistant, and are not guaranteed to give better performance than a single card.

Also until nvidias "big bang 2" drivers come out SLI restricts multiple monitor use.