I too got that board. Running 2 sticks of 256 mb 7ns cas2 ram, and one 128 mb apacer. Running great at 133 mhz cas2 4-way interleave on.
The board supports 1.5 gb ram and with 3 ram slots it should be able to use 512 mb sticks.
My system is rock stable with an athlon 700@850 and 640 mb ram, 4 pci cards, 3 harddrives, 1 dvd, 1 cd rom and 2 cd'rws.