Futuremark 3DMark Vantage
We minimize the CPU’s influence by using the Extreme profile (1920x1200, 4x FSAA and anisotropic filtering).
The Radeon HD 4870 X2 does not get any faster in 3DMark Vantage when its GPUs are overclocked by 50MHz. This must be due to the lack of memory frequency growth despite the tremendous combined bandwidth of the two GDDR5 memory banks.
It is only in the second that we can find a 2-3% growth of speed whereas the first test doesn’t show any difference. The individual tests agree with the overall scores.