vash

i have just built a crossfire system i have x1900 Cf edtion and x1900xtx i have the ngo drivers and i down loaded the ccc from ati but when i ran 3dmark o6 i got a score of 3000 with 2 cards and with 1 card i get almost 6000 and i dont overclok and i enabled crossfire in the ccc so should i use the both the drivers and ccc from ngo or does it matter and i use tinyxp vista edtion as my Os

my system is

x1900cf
x1900xtx
2gig ocz soe ram
asus a8r32 mvp deluxe mobo
250 gig hdd seagate barracudda
amd 3800+ dualcore