The G41 chipset (Dual Core/Core 2 Duo/Core 2 Quad) boards require double-sided low density (2Rx8) 4GB modules. They WILL NOT post with single-sided high density (1Rx8) 4GB memory installed.
I have a G41M and a P45 board and they both require double-sided low density 4GB (2Rx8) memory modules or...