Set in the immediate aftermath of the zombie apocalypse, L4D offers four expansive “movie campaigns” that challenge you and your fellow survivors to battle thousands of swarming zombies as you travel across the rooftops of an abandoned metropolis, through rural ghost towns and pitch-black forests. In addition to the movie campaigns, Left 4 Dead features a Versus mode that allows you to play as the Boss Zombies.
New technology dubbed “the AI Director” is used to generate a unique game-play experience every time you play. The Director tailors the frequency and ferocity of the zombie attacks to your performance, adjusting pacing, special effects and audio on the fly.
The highest settings were used for testing, on the final sections of Dead Air and No Mercy.
As you can see here, the HD4670 played much better than the 9600GSO at a resolution of 1280×1024, but in reality, the game could not be played at highest settings at that resolution on the GSO; it would stay at 50+ fps most of the time and the game would constantly halt half the times you shoot. For up to 20 seconds it would just freeze and this behavior continued until I set the setting down almost to the lowest with no AA or AF at all and other settings low as well. I’m not entirely sure if this is a driver issue or not, but the HD4670 plays consistently well with no issues, so the winner is clear for this game.