New BH7 ram problem. 3 sticks of 333?!

I picked up a BH7 yesterday got it installed, but I've got a memory problem. I wasn't aware that the BH7 dosn't support 3 sticks of 333. Only 2x333 or 3x266. I've got 3 sticks of 333, so my question is, would it work if I put in 2 sticks of 333 and 1 266 stick? I've got 3 512mb 2700 dimms and when I put them all in yesterday, it just came up as 1gb. I can trade the 1 512 for a 512 266 but I just wanna make sure that'll work.