I don't understand the situation of performance level, I don't know how the situation is with the other Intel chipset but why you can have better PL (also 2/3 level PL!) with higher memory frequency? It seems strange that with 1:1 divider and most conservatives FSB and ram frequency you can't have almost the same PL of a most tighter setting.
What is it?
Something related to chipset... something related to Asus mobo or bios... or this is the normal situation and with 1:1 divider you can't use a best PL level that, paradoxically, you can obtain with tighter settings?