sorry for second post but i wanna be more specific..
I was using the 2 x 1gb corsair ram till today when i went and bought the 2 x gb kingmax piece.... i came home and put the 2gb piece in my motherboard: pc started but monitor was black. Turned the pc off and removed both the 2x 1gb pieces, then started the pc again: it worked fine. Turned it off and started playing with the ram slots. Put the 1gb2gb1gb= black screen , put 2gb1gb1gb=black screen, i put 1gb1gb2gb=black screen, i put 2gb1gb and left 2 slots empty removing one of the 1gb piece...worked fine. dunno if this makes any sense . my english is not that great.