If money is no object today-and won't be a year or so from now when you want AGP 8X and S-ATA drives, the best stability and performance comes with 1066 RDRAM and the I-850E chipset. The Asus P4T533 is the board of choice in that configuration, and it is very fast.
But the 850E will be the Intel's last RDRAM chipset for desktop systems. Beginning next year they will only make Rambus chipsets for server boards, and that means when you want S-ATA and AGP 8X, you'll also need to replace your memory. (SiS has announced plans to pick up the desktop RDRAM market after Intel leaves, but most analysts are taking a wait-and-see attitude on this board actually going into production.)
My choice would be a DDR setup using an Asus P4B533E or Abit IT7 MAX. Both can be pushed to the performance level of a 1066 RDRAM system, and have exceptional stability. And with quality memory, you should be able to transfer your RAM to a Dual DDR board when they become available.
My choice for that memory would be Corsair XMS3200 CAS2.
BHD