The nVidia site has a page about MS hotfixes for issues with Vista/ForceWare drivers/etc.
It sounds to me that you may have installed the FW163 drivers without the hotfix file(?)
All the details that I found are at:
HERE (nVidia Hotfix Page)
Hope that helps your score. Peronally, I don't put much faith in MS benchmark programs.
3dMark, PCMark, Sandra, those I think give you a better idea of what your machine can do...
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A veteran - whether active duty, retired, national guard or reserve - is someone who, at one point in their life, wrote a blank check made payable to "The United States of America", for an amount of "up to and including my life".
That is
Honor, and there are way too many people in this country, who no longer understand that...