Performance in First-Person 3D Shooters
Aliens vs. Predator
This game runs in DirectX 11 mode with the highest graphics quality settings.
The GeForce GTS 450 SLI tandem is almost as fast as the single GeForce GTX 470. The tandem is cheaper (it costs twice the price of a single GTS 450, i.e. about $260 whereas a GeForce GTX 470 costs $300 or more) but the small difference in price is hardly worth the trouble of building and maintaining a multi-GPU configuration.
Battlefield: Bad Company 2
The SLI tandem overtakes the GeForce GTX 470 and is close to matching the Radeon HD 5870. Again, the lower price is the main advantage of the multi-GPU configuration while its lower usability and compatibility are its main downsides. Besides, its performance at 2560x1600 is rather poor.
Call of Duty: Modern Warfare 2
We don’t see anything new here. The GeForce GTS 450 SLI is quite fast but not as fast as to justify the $40-50 economy compared to the comparable single-chip solutions. Besides, it slows down more than its single-GPU opponents at resolutions higher than 1920x1080.
The advantages of the GeForce GTS 450 SLI are as unclear as in the previous tests: it is comparable to the GeForce GTX 470 in performance at popular resolutions but loses its ground at extremely high display modes. Thus, the only possible reason for building such a tandem is when you have one GeForce GTS 450 and add another one later on as a way to upgrade your graphics subsystem for little money.