Benchmark Results: Left 4 Dead
This one has never been particularly GPU-limited, so it’s hardly a surprise that the Radeon HD 4850, Radeon HD 4770, Radeon HD 4830, and GeForce GTS 250 perform at least somewhat similarly. Any of those four cards will serve up a satisfying experience if you keep anti-aliasing and anisotropic filtering turned off.
The Radeon HD 4850 and GeForce GTS 250 hang in a tight grouping as additional eye candy is applied. The Radeon HD 4770 falls back a little bit, but still manages to deliver playable frame rates through 1920x1200. The only card incapable of keeping up is the Radeon HD 4670 with 512 MB of GDDR4 memory.