G.SKILL Ripjaws Series 4GB (2 x 2GB) 240-Pin DDR3 SDRAM 1600 (PC3 12800) Desktop Memory Model F3-12800CL8D-4GBRM 4GB DDR3 1600MHz Dual Channel kit Suitable for Intel P55 chipset Timings 8-8-8-24, 1.6V PC3-12800 specification Two matched 2GB modules with G.Skill Ripjaw heatsinks