Bought 2 4 gigs of hynix 4gb 2Rx8 pc3 - 10600S - 9 - 10 - F2 and only when i put both sticks of ram in my computer wouldnt even turn on so i took 1 of the sticks out and kept an old 2 gig of ram in there and it booted up. Why wont both 4 gig sticks of ram work together?