I'm not going to run at resolutions like that, as I'm staying native and just ran a quick blast of the stress tests.
CS:S 1920x1200 4xAA/8xAF and set to Best Image Quality, v-sync set as 3D application controlled with HDR full. Gamma AA and Trans AA Supersampling on everything High appart from water which I've always prefered just to reflect world. 105fps.
Lost Coast same settings as above, 60fps.
System: XP Pro, AthlonXP3200+, Abit NF7-S, 2GB PC3500, 7800GS+, Audigy2 ZS.