I have no more money to buy 8gbG.Skill Sniper DDR3 8 GB (2 x 8 GB) dual channel ram. I have in budget i wantG.Skill Sniper DDR3 4 GB (1 x 4 GB) at this time and 4gb later to run in dual channel mode.so say me G.Skill Sniper DDR3 4 GB (1 x 4 GB) is compable for later upgrading in dual channel mode?