The Performance Boost
NVIDIA ran a performance comparison using a benchmark with 15,000 boulders in the scene. As you can see, NVIDIA is claiming a 10X increase in performance!
Of course, that's NVIDIA's word on the performance boost we can expect from offloading effect physics to the GPU. Needless to say, you are unlikely to encounter a scene with 15 thousand boulders bouncing around!
SLI For Developers
NVIDIA also made a point of telling us why SLI is not only for the hardcore gamer who want nothing but the best. Even game developers should make use of SLI. This is because SLI will allow game developers to develop games for the next generation mainstream cards.
The performance level of today's SLI cards will be more or less what we can expect from a single next-generation card. Game developers can therefore design games around what's expected from the next generation cards, without actually waiting for them.
Of course, with SLI physics thrown in, game developers can also reduce their dependency on the CPU to deliver even better graphics. They can design their games around the graphics processor, instead of the CPU. Exactly what NVIDIA would like, of course!
There's no word on when we can actually run SLI physics on our own systems. But NVIDIA says that both games and drivers that support SLI physics will be available by the end of the year.
Like SLI, SLI physics will come with optimized profiles for various games that support it, but it's not necessary. As long as the game and driver supports SLI physics, it should work out of the box.