Doom3
Doom3 uses AFR and rightly so. Framerates are always high enough that the latency issues inherent with AFR are masked and gameplay is unaffected. NVIDIA's showcase games title runs very well indeed with SLI.I also try out Ultra Quality mode for kicks. High and Ultra quality apply 8x anisotropic filtering at all times, so I use resolution increases and anti-aliasing to see performance scaling.
My thanks to Damage at Tech Report for allowing me to use one of his demos for my SLI testing. Visit those fine folks here.
High Quality
When we're slightly CPU limited we're limited to an 11% performance increase. That carries on rising however, getting you 81% more performance at 1600x1200. That should make 1600x1200 with 4x AA at Ultra Quality playable.
Ultra Quality
And it does, the framerate rarely dropping below 60fps (a lovely figure, matching the Vsync refresh on my LCD at 1600x1200) at any time. SLI lets me play Doom3 as iD intended. 78% more performance is measured at the highest setting.
Remember that effective memory in AFR mode isn't 512MB, it's still 256MB. So with over 500MB of data per level, there's still some extra performance to be had in Doom3 from a larger framebuffer, over and above what SLI gets you.
