Corsair DDR3 1600MHz 4GB (CMV4GX3M1A1600C11)

Corsair ValueSelect 4GB DDR3 SDRAM Memory Module - For Desktop PC - 4 GB (1 x 4GB) - DDR3-1600/PC3-12800 DDR3 SDRAM - 1600 MHz - CL11 - 1.50 V - Unbuf

Corsair CMV4GX3M1A1600C11 4GB (1 x 4GB) 240-Pin DDR3 1600Mhz PC3 12800 Desktop Memory 1.5V