Still one of the most demanding games on the market, Oblivion was tested at 2560x1600 and 1920x1200 using the following settings. HDR was used, however not in conjunction with antialiasing.
Oblivion Engine Settings
The picture below shows part of the area used to test. Oblivion gates offer some of the most demanding lighting and particle effects in the game so it only makes sense to test around one. Along with the gate, there is a large smoke plume, a few random fires and lots of grass and trees to stress the cards.
Click Image to Enlarge - 2560x1600 (954KB)
Below are graphs showing the minimum, average and maximum framerates at 2560x1600 and 1920x1200.
Oblivion Average Framerate Scores
Unlike the Source Engine, raw speed has more of an impact in Oblivion as the graphs above show. The overclocked settings offer vastly improved performance at both levels of clock speeds at 1920x1200. At 2560x1600, the aggressive clocks just edge out the 640MB GTS while the factory overclocked settings lag just slightly behind. All in all, clock speeds can make up for less memory in Oblivion.
The below graphs show the framerates of each run-through at both 2560x1600 and 1920x1200.
Oblivion Frames Per Second
Considering how amazing Oblivion looks, I figured the 320MB GTS would suffer similar to how it had in the Source engine. Surprisingly, the 320MB GTS was able to make up for its lack of memory with the insane clock speeds it achieved.