It is not allowed to install a DDR3 memory module into DDR2 slot or install a DDR2 memory module into DDR3 slot; otherwise, this motherboard and DIMM may be. asrock n68c-s ucc manual. This motherboard provides two pin DDR2 (Double Data Rate 2) DIMM slots and two pin DDR3 (Double Data Rate 3) DIMM slots, and supports Dual Channel. .