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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Kids in the back seat can cause accidents.
Accidents in the back seat can cause kids.
Moral: Drive a two seater