how to make RDram 1066 work?

i just built a system. i have a P4T533-C, windows XP pro sp1. 800jb hard drive, aiw 9700 radeon.
my problem is that according to 3dmark 2003 my memory is running @ 800MHz , i bought 2 stick of 256 Mb 1066Mhz rdram, how do i make it work @ 1066?? is there a setting in BIos or something.

PS. my frot side bus is @ 533MHZ.

thanks

Doubt you'll see this, but the answer to this question is to update the firmware (just go to the latest, I'm not sure which one exactly fixes this issue). My 1066 wasn't showing up in anything as being 1066, so I updated my firmware and then it showed up as 1066.