ati x1600 td256e vista

Thought I should repost here as my main theme is gaming....
Interesting Video and other results in comparison with my XP machine at PCPitstop.com
The XP....... MSI Nvidia 5900 128MB video card scored
328 million pixels per second
The Vista MSI Ati X1600 TD256E scored
66.7 million
Lot`s of difference there.
Hard drive results were disappointing too. The Vista machine only scored 77% of similar drives. I have thought it sluggish since I formatted with Vista (far too quick imho). I used Max Tools to test the drive it is perfect, has to be the format or the OS imho. Every other I`ve spoken to testing Beta atm say`s the same best results are when the drive is formatted using another OS not the apparently quick format Vista uses.

Sorry didn`t post machine specs to differentiate.
Vista
AMD 64 Sempron 3100+ 1GB Ram MSI-7228 mobo Ati MSI X1600 TD256E 120GB Maxtor hard drive
XP
Intel P4 Northwood 3 GHz MSI 875 Neo P mobo 512 MB Ram Nvidia MSI 5900 TDE 128MB Graphic card Sata II hard drive 160GB ( The board is only sata I but it has a vast effect on everything seeing a score of over 130% on PC Pitstop)
Games on the Vista....
Half Life 2 Counterstrike FEAR
All graphics appear clean but games can be stuttery as it calls to the drive.