Help: GA-K8N Pro Memory Issue

I purchased the GA-K8N Pro with two sticks of 400 MHz Ram and at first was
unable to boot. So I disconnected everything, removed the board and tried
again. I then was able to boot but when I tried to install the OS, both XP
and 2K and continuously rec'd a memory dump error. I had 3 other sticks of
DDR 333MHz ram so I tried these all together at first and rec'd continous
beeps. I then tried one at a time and was able to finally get one of the
256s to load XP but to my dismay was unable to find out what type of RAM
should I have purchased on the Giga-byte website. Any suggestions would be
appreciated as 256MB of RAM is ok but will not suffice for long.

Regards

Sam
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