Team Fortress 2 at 2560 x 1600 was a similar story to the 1920 x 1080 results... The GTX 550 Ti, GTX 650, and GTX 680 of the tested hardware was all pushing playable frame-rates while the GTX 460 was acting funky and the GT 520 and GT 610 were running at a snail's pace. The GPUs had performed much better in other similar quality OpenGL Linux tests like Unigine, id Tech, and Xonotic workloads. The next large round of Linux GPU comparison results will come in the budget GeForce GT 610 Ubuntu review.
You can compare your own system's Team Fortress 2 performance on Linux to these NVIDIA reference results by having Steam/TF2 and the Phoronix Test Suite and then proceeding to simply run phoronix-test-suite benchmark 1311082-SO-NVIDIATEA11 for carrying out a fully-automated comparison in the same environment as was used for this article.
Stay tuned for the next round of results with AMD Radeon hardware to see if there are similar odd performance issues for some GPUs.