The P4TE is designed for 100 FSB, and therefore the PC800 RDRAM and the P4-A. The P4T533-C (NOT its troubled sibling the P4T533) is essentially the same, except it is improved some (with the I850E chipset, better clock generators, etc) for a 133 FSB, and therefore the PC1066 RDRAM and the P4-B. Both these boards use the older RDRAM modules that do need to be installed in pairs. If you're looking for 512 Mb total, then get two 256 Mb sticks. There are four memory slots on the board, so you can add another pair later if you want.
Of course, people have been using 100 FSB boards like the P4TE to overclock by increasing their FSB, and some lucky folks have even reached the 133 FSB level with their PC800 RDRAM and P4-A's. But there are other less lucky ones who haven't. If I were already buying a 133 FSB board like the P4T533-C, then I'd carefully compare the difference in cost between the 100 FSB and 133 FSB memory and CPUs. Perhaps the extra bucks is worth the guarantee of reaching at least 133 FSB.
Good Luck