Performance in Semi-Synthetic Benchmarks
Despite 1280x1024 resolution, Palit GeForce GTS 250 1GB outperformed GeForce GTS 250 512MB by far more than a simple measuring error margin. The results of individual tests showed that the highest performance boost can be seen in SM2.0, while there was almost none in SM3.0/HDR tests. We could even see a slight lag caused by slightly lower memory frequency.
Futuremark 3DMark Vantage
We minimize the CPU influence during 3DMark Vantage tests by using the Extreme profile (1920x1200, 4x FSAA and anisotropic filtering). We also publish the results of the individual tests across all display resolutions to provide a complete picture.
3DMark Vantage creates testing conditions that are the closest to the current realities, so we see the benefits of larger memory capacity as well as of additional overclocking. In the latter case Palit GeForce GTS 250 1GB manages to outperform Radeon HD 4850 significantly, at least the model equipped with 512MB of memory.
Although we could see practically linear performance increase in the total score charts, the results of individual benchmarks show that complex GPU and memory overclocking have a much great effect on performance than the increase of the memory capacity from 512MB to 1GB. This is true at least in resolutions up to 1920x1200.