G.Skill Aegis 4GB 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model F3-1600C11S-4GIS F3-1600C11S-4GIS DDR3 1600 (PC3 12800) Timing 11-11-11-28 Cas Latency 11 Voltage 1.5V