Product Detail 4GB DDR3 1600MHz Dual Channel kit Low latency CL7 kit Suitable for Intel P55 chipset Timings 7-8-7-24, 1.6V PC3-12800 specification . The "G.Skill Ripjaws F3-12800CL7D-4GBRM - Memory - 4 GB : 2 x 2 GB - DIMM 240-pin - DDR3 - 1600 MHz / PC3-12800 - CL7 - 1.6 V - unbuffered - non-ECC" is best product for you. We recommended G.Skill Ripjaws F3-12800CL7D-4GBRM - Memory - 4 GB : 2 x 2 GB - DIMM 240-pin - DDR3 - 1600 MHz / PC3-12800 - CL7 - 1.6 V - unbuffered - non-ECC