What distinguishes the ASUS ENGTX460 TOP from the rest of the pack is a proprietary cooling system and the ability to tweak voltages.  It is overclocked out of the box, though at 700MHz, or 25MHz higher than reference GPU, it is unimpressive and neither the shaders 50MHz bump to 1400MHz nor the 80MHz effective jump to 3680MHz change the performance in any significant way.  All is not lost with this TOP, once [H]ard|OCP started their own overclocking experiment they hit 895MHz on the GPU, the shader went to 1790MHz, and the effective memory speed hit 4120MHz.  At that point they saw a difference in benchmark performance.

“The ASUS ENGTX460 TOP 768MB delivers boosted frequencies, a unique cooling solution with large 8mm heat-pipes, and Voltage Tweak. However, is that enough to best a reference GTX 460 768MB and an ATI Radeon HD 5770 1GB?”

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