what has happened is you have placed your ram incorrectly what you need to do is find DIMM slot 1 and place your higest ram stick in it, then place in the rest of your ram, in decending order preferably.
what happens is when your bios starts it reads the first bit of ram it finds then it presumes anymore ram is of equal vale, or lower....hence why you need to put the highest ram in slot 1.
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crap i dident read your post right...sorry, not a clue.