I almost bought a motherboard I forget witch one that could only use a MAX of 2 Sticks of PC3200 at any given time, so I changed it and bought a different one that I could put 3 sticks of PC 3200 Ram in it, because I will be getting more RAM for my computer and moving this RAM into it,
Sorry I know this really doesn't help you but I thought I'd share it with you.
I have PC3200 Ram running with my daughters Sempron 2800+ at PC2700 Speeds but if it says the board only supprts ddr266 (pc2100) ram, you might want to make sure.