XP vs Vista Speed Test

I used Passmark benchmarking software. It tested CPU use, disk access,
graphics, memory access. On the same machine (triple boot to XP, Vista 32,
Vista 64) the numbers were virtually identical for all three with the
exception of the graphics. Graphics performance changed as I updated drivers
(sometimes up, sometimes down) but in general Vista seems to be faster with
the graphics (ATI PCIexpress card). There was no difference in performance
between XP, Vista 32, Vista 64 for the 32 bit benchmarks. When I ran the 64
bit benchmarks (only in Vista 64) they were significantly better for memory
access and graphics but no difference in CPU or disk access.
There seems to be no improvement in CPU use, Memory access or disk access
between XP or Vista 32 bit, although there is a significant difference in
memory access with Vista 64 bit.