Half-Life 2 - Route Kanal
Our first Half-Life 2 demo is a longish section of the Route Kanal sequence early in the game. It combines a number of effects, including reflective water and the flashlight, with a lot of running around in simple, dark corridors and a few outside areas.

Half-Life 2 does for the ATI cards what Doom 3 does for the NVIDIAs. The Radeon X800 XL shadows the GeForce 6800 Ultra without antialiasing and aniso filtering, then it steps in front of the Ultra when 4X AA and 8X aniso are enabled. The 6800 GT runs well behind the XL, and the vanilla 6800 is even further back.

Saving grace for NVIDIA: even the 6800 GT runs this game at over 60 frames per second at 1600x1200 with 4X antialiasing and 8X aniso. Most of these cards are playable at essentially max settings for this game. Subjectively, on the Radeon X800 XL, I prefer 1280x1204 at 4X/8X for the best mix of playability and eye candy. 1600x1200 is playable, but not always smooth as glass.