OCIA.net has published an article on Overclocking the NVIDIA 5900 XT/SE Series Video Cards.

I started at the default 400Mhz GPU / 700Mhz Mem and scaled up to 505Mhz GPU / 960Mhz Mem -- the highest clocks are not stable for prolonged use, though they most likely could be with a better cooling solution, like water.. so I included them anyway. I did 4 steps because not everyone will get the same results when overclocking their card, every single card is different, sad but true.

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