I just bought new 4gb ddr3 with 1333mhz, and my pc won't turn on. My motherboard is asrock n68c- s ucc and is said that it can support up to 1600mhz. What do I need to do? By the way when I put my old ddr2 memory stick it will turn on, but when I put the new ddr3 memory stick, it won't turn on