Benchmark Results: Left 4 Dead
All of the tested cards have enough muscle to plow through Left 4 Dead, even at 2560x1600, and the Radeon HD 4890’s advantage over the Radeon HD 4870 remains fairly constant. Interestingly, the 512 MB board is able to outperform the 1 GB model at the two lowest resolutions and match it in the highest setting. Nvidia’s GeForce GTX 260 Core 216 hangs right with that 1 GB HD 4870 as well.
The Radeon HD 4870 X2 remains CPU-limited at the two lowest resolutions, but all of the other cards scale more clearly when AA and AF are turned on. 10%. 10%. 10%. You get about 10% more speed for a 30-40% jump in price.