I didnt look up the mobo, but I bet thats the case, I have one, and its a year or two (or 3.5) old and it WILL NOT use any ram over 1gb total. It would say in the instruction manual, but Im sure that is what it is, and BTW just because it has 4 slots doenst mean a thing, it could be 4 things of 256 that they want you to use!
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Heaven has a beer volcano and stripper factory
Hell is the same, but the beer is stale and the strippers have STDs