G.Skill F2-6400CL5D-4GBPQ 4GB 2 x 2GB PC2-6400U DDR2 800 Dual Channel Memory Kit Brand: G.SKILL Dual Channel Memory Kit Model: F2-6400CL5D-4GBPQ Capacity: 4GB (2 x 2GB) Type: 240-Pin DDR2 SDRAM Speed: DDR2 800 (PC2-6400U)