The last time I had a bunch of memory errors, I tried everything, ripped my machine apart, ran the memory through
www.memtest86.com's utility, swapped the PSU, yanked every card I could, and then in a fit of curiosity, told my bios to reload the defaults, changed my clock speed up to where it should be (old KT133, defaults to 800mhz, I clocked it back up to 1.2), that's all I changed and the problem went away.
Weird, but maybe the case. The board is more or less identical to the 266 flavor of the board with a RAM bus upgrade, that's it. Everything on the chipset is supported under 7.2.
If that doesn't work, first off its yelling about memory addressing so run memcheck, post back, it can get sorted.
Cheers,
Finegan