Explosive Labs has posted a guide about modding your FX5900 into a FX5950 Ultra

Some pretty interesting results I came up with. With the card running at the same speeds results for 3DMark03 and Q3A drop with the A380U BIOS. With the new BIOS though I was able to overclock the card even some more. This seems to be the same thing happening to members over at the Futuremark forums and here is what they have come up with. Reason why we see a decrease in results is most likely because that with the new BIOS memory timings are more relaxed. That is most likely the reason I am able to overclock the memory even higher with the new BIOS. For the core it seems like the new BIOS gives a bit more voltage to it allowing me to clock it even higher. No solid evidence yet but certainly a good explanation for the results.

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