OCC has published a review on the ASUS P7H55D-M EVO
A quote from the article:
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One thing it did lack was that it couldn't match the H57 model in overclocking. This was a bit surprising as both boards use ASUS's Xtreme Design and share a very similar VRM area. Still, the ASUS P7H55D-M EVO was only 200MHz shy of the 4.5GHz overclock of the more high-end board and it was able to produce the third best overclock this chip has seen.
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