PC2 6400 posting as 4300 when system overclocked?

pchoi04

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Apr 2, 2007
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I'm running the Corsair TWIN2X2048-6400C4 and when my BIOS is set to default on the post screen it lists my system specs and everything looks fine. But when I start overclocking and tweaking my memory and such its posting as PC2 4300... Why is that? Am I doing something wrong?