Benchmarks - High Quality AA and AF
To test the visual effects capabilities of the card, we enabled 4xAA (anti aliasing) and 8xAF (anisotropic filtering). These technologies are used to improve the overall look of each rendered screen. Anti aliasing smoothes jagged edges created by near-vertical and near-horizontal lines, while anisotropic filtering improves the appearance of non-linear surfaces and texture mapping - reducing visual artefacts near vanishing points for example.
As the level of filtering applied increases, the graphics card has to work much harder to render each frame. For example, depending on the filtering method used, 4xAA can require the card to render the same screen four times before the final output is shown. Needless to say, this can (and usually does) have a substantial impact on a card's ability to render frame quickly, and the onboard supporting 3D architecture become vitally important - these transformations simply can't be made on the fly by the GPU alone.
Typically, you expect to find that at the same resolution, frame rates are lower with AA/AF enabled. At lower resolutions, however, the overhead is not as dramatic as with higher resolutions - rendering 1600x1200/4xAA/8xAF is exponentially harder than 1024x768/4xAA/8xAF. Much more than the difference between rendering 1024x768/noAA/noAF and 1600x1200/noAA/noAF.
By and large, the HIS X700 handled the visual filtering fairly consistently across each test - gaming frame rates were substantially worse than the 1024x768/noAA/noAF results, and marginally better than the 1600x1200/noAA/noAF results.
Just for fun, we tried running the Half Life 2 timedemos at 1600x1200/4xAA/8xAF. The card made a valiant attempt but the performance got progressively worse until the rendering engine gave in and the application crashed. Don't try and play anything with these settings, unless it's Doom (the original!).