problem with ram running in dual channel mode

[RambunctiousAmoeba]

I just finished building my new computer and hit a little snag; my ram won't run in dual channel mode.(OCZ 512x2) If I run either stick by itself or both in dual channel the computer runs fine, but if I try to run them in dual channel the computer gets just past the black windows loading screen and freezes on a totally black screen. Can anybody help me with my problem?

DFI LanParty nf4 Ultra-D
Athlon 64 3200 "Venice"
512MBx2 OCZ "Value Series" CAS 2.5