SLI technology brings its positive effect to Half-Life 2, too. This effect is less conspicuous in low resolutions where the load on the graphics subsystem is low. In high resolutions, however, the performance in the SLI mode is 50-60 percent higher than that of the single card.
NVIDIA’s multi-GPU technology has an even bigger effect in the “eye candy” mode – up to 80 percent. Yet the SLI configuration has a really big advantage over the high-performance solutions from ATI Technologies in 1600x1200 resolution only.
The second scene from Half-Life 2 that we use in our tests depends more on the CPU speed than the first one, so it’s harder to see the SLI effect here, at least in the “pure speed” mode.
SLI technology’s speed bonus is evident in the “eye candy” mode, in 1280x1024 resolution and up, especially with the system consisting of two GeForce 6600 GT cards. The pair of GeForce 6800 Ultra cards outperforms the RADEON X850 XT PE and X800 XTPE in 1600x1200 resolution only, but NVIDIA’s SLI seems to be at its best under such hardest conditions.