We tested Oblivion by manually playing through a specific point in the game five times while recording frame rates using the FRAPS utility. Each gameplay sequence lasted 60 seconds. This method has the advantage of simulating real gameplay quite closely, but it comes at the expense of precise repeatability. We believe five sample sessions are sufficient to get reasonably consistent and trustworthy results. In addition to average frame rates, we've included the low frames rates, because those tend to reflect the user experience in performance-critical situations. In order to diminish the effect of outliers, we've reported the median of the five low frame rates we encountered.
We turned up all of Oblivion's graphical settings to their highest quality levels for this test. The screen resolution was set to 1920x1200 resolution, with HDR lighting enabled. 16X anisotropic filtering and 4X AA was forced on via the cards' driver control panels. Since the G71 GPU can't do 16-bit floating-point texture filtering and blending in combination with antialiasing, the cards based on it had to sit out these tests.
For this test, we strolled around the outside of the Leyawin city wall, as show in the picture below. This area has loads of vegetation, some reflective water, and some long view distances.
I should say that when playing through this sequence, the GTS 320MB cards didn't feel especially slow, despite their FPS lows in the teens and low twenties. Those lows seemed to come when the game engine decided to scale up the level of detail as we got closer to a group of trees or the like. Still, the 640MB card vastly reduced the severity of those hiccups.
Rainbow Six: Vegas
This game is a new addition to our test suite, notable because it's the first game we've tested based on Unreal Engine 3. As with Oblivion, we tested with FRAPS. This time, I played through a 90-second portion of the "Dante's" map in the game's Terrorist Hunt mode, with all of the game's quality options cranked.
Ghost Recon Advanced Warfighter
We tested GRAW with FRAPS, as well. We cranked up all of the quality settings for this game, with the exception of antialiasing, since the game engine doesn't take to AA very well.
Admittedly, asking some of the less expensive cards to run this game at the settings we've used is a bit much. The game identified the Radeon X1900 XT as having only 256MB of memory and refused to set the display resolution to 2560x1600. Rather than fuss with the config files, we just decided to have the X1900 XT sit this one out.