Get problem when crossfire x1950 pro on XP

[too9s]

Is there any one try to crossfire x1950 pro on XP?
I think I get some problem about drivers.
If I use Catalyst 8.4, it can enable crossfire but can't work fine in 3dMark06/05.
The marks lower than disable CF, but GPUZ display CF is enable.

I try to change other version catalyst 7.11/6.12.
6.12 can work fine,but 7.11 get some problem.
Any other version catalyst can let crossfire work fine on XP?
6.12 seems too old...Orz

My PC
MB: DFI DK 790FX M2RS
CPU:AMD 5000+ black edtion
RAM: UMAX DDR800 2G*2
Video Card: PowerColor X1950 pro 256MB*2