Serious Sam: Average FPS Over Time
The following graph looks at the average FPS for each second of the Serious Sam: Second Encounter Citadel demo under OpenGL. 640x480 represents the geometry limited case, 1600x1200 the most fill limited and 1024x768 as the medium. Also included is a Radeon 8500 at 1024x768 to gauge performance.
On the 9700 PRO both 640x480 and 1024x768 track each other fairly closely as the 9700 is hardly fill rate limited in this title at 1024x768. In both these resolutions there isn't a case where the FPS drops below 60.
At 1600x1200 the 9700 PRO is tracking somewhat below the 8500, with the excessive peaks shaved off somewhat because of fill rate limitations. Here we can see that the 9700 PRO is just a little below the performance of the 8500 at 1024x768, most of the time remaining over 50FPS.
Pixel Shaders
To take a look at the Pixel Shader performance we'll use 3DMark2001SE' three pixel shader tests.
| FPS | 640x480 | 800x600 | 1024x768 | 1280x1024 | 1600x1200 | |
| Pixel Shader | 9700 PRO | 196.8 | 179.7 | 183.3 | 129.3 | 94.3 |
| 8500 | 193.7 | 151.3 | 101.2 | 64.7 | 46.5 | |
| Nature | 9700 PRO | 162.1 | 133.5 | 96.7 | 67.2 | 48.5 |
| 8500 | 90.2 | 65.3 | 43.8 | 28.3 | 18.7 | |
| Advanced Shader | 9700 PRO | 307.0 | 250.9 | 189.1 | 133.5 | 95.1 |
| 8500 | 112.4 | 97.7 | 79.9 | 60.7 | 44.9 |
| Difference | 640x480 | 800x600 | 1024x768 | 1280x1024 | 1600x1200 | |
| Pixel Shader | FPS | 3.1 | 28.4 | 82.1 | 64.6 | 47.8 |
| % | 2% | 19% | 81% | 100% | 103% | |
| Nature | FPS | 71.9 | 68.2 | 52.9 | 38.9 | 29.8 |
| % | 80% | 104% | 121% | 137% | 159% | |
| Advanced Shader | FPS | 194.6 | 153.2 | 109.2 | 72.8 | 50.2 |
| % | 173% | 157% | 137% | 120% | 112% | |
On the 'Pixel Shader' test both the 8500 and 9700 PRO start out at fairly similar levels, which is indicative of a CPU/system limitation at low resolution. As the resolution scales up the we can see the performance advantage of 9700 PRO open up somewhat, having twice the performance of 8500 at 1600x1200.
With the Nature test we can see that 9700 PRO immediately starts of with a fairly large advantage over 8500. The Nature test is both a Vertex and Pixel Shaders test so its not surprising to see the extra Vertex performance of 9700 PRO assisting at low resolutions. As we scale up the resolutions the FPS drops for both cards quite significantly, but the percentage difference goes up. By 1600x1200 9700 PRO has a 159% performance advantage over 8500.
With the Advanced Shader test, which uses Radeon 8500's native PS1.4 abilities, we can see a similar trend as with the Nature scene, albeit accentuated. At low resolution 9700 PRO nearly has a 3 times performance advantage over 8500, which would largely be due to the Vertex Shader. By 1600x1200 9700 PRO is still twice as fast as 8500 at 95FPS.
So, does the increased number of Pixel Shader Operations per cycle help at all? Well, although at fill limited situation we are seeing performance improvements more or less in line with the increase clock rate, fill rate per clock and bandwidth, we have to remember that Radeon 9700 PRO can only apply the same number of textures per clock as 8500 and so to maintain a 100% advantages in all cases at 1600x1200 something is going right!
