P4T533-C has better memory clock generators that are rated at 600MHz, while the ones on the TH7-II are rated at only 400MHz. P4T533-C also has a USB 2.0 controller.
I have the P4T533-C and a 2.4B 533 @2555 and 1066 memory at
1136 my 2001SE score is 12124 with out overclocking the
Gforce 4 4600. The chip will run at 2700 with memory at 3
but my 1066 Kingston 32N will not run at 1200 Mhz.
You're looking at RDRAM vs. DDR RAM. The BD7 and BD7II will run the RAM at 400MHz on a 150MHz FSB while locking the PCI/AGP bus. As I've been saying many times, the best option for an overclocked P4 1.6A is a DDR board, but anything faster, you'll want RDRAM.