I just finished putting one together.
MSI KT3 Ultra
512 OCZ PC3000 ram
amd xp +1700
It took me three days to get the bios settings just right. It would not load the os, win xp home. Once I set it up right it runs great.
Check google for msi kt3 setup guides, there is a msi forum @ http://cweb.msi.com.tw/eforum/tip/forum_tip.htm. I didn't find this to be of much help, but you might find some sites that are helpful. have fun