"This article will not cover te quality of the gameplay experience, as is our usual fare. Instead, today’s preliminary tests are to find out who has the fastest video cards for playing Half Life 2 in apples to apples benchmarks. This will dispel many of the myths being rumored about Half Life 2 performance as we cut to the chase and see who has the fastest Half Life 2 AGP video card."
HardOCP used custom timedemos to simulate normal gameplay.
6800U and x800xtpe trade blows depending on map (6800U does better on canals, x800xtpe does better on coast)
6800GT beats x800pro across the board
"As for calling one video card a “winner” over the other, it just does not seem feasible and would likely be irresponsible to do so. ATI’s X800 series has not thrashed NVIDIA’s 6800 series silicon as many expected. Half Life 2 simply plays great on video cards from both NVIDIA and ATI. So let’s make this clear. The ATI Radeon X800 series of video cards will deliver a stellar Half Life 2 gaming experience. Also… The NVIDIA GeForce 6800 and 6600 series of video cards will deliver a stellar Half Life 2 gaming experience. There are simply no losers to be found if you have recently upgraded your video card. You have likely all made good gaming investments."