Rokins, you can insert about any ram into your computer, if the ram sticks are of different speed then all sticks will reduce speed to match the speed of the slower stick. You should be able to insert any 2gb ddr3 stick into your computer, its unlikely that it will not work even if its not a kit. If three single sticks cost less then one kit of 3 pieces then go for the single sticks, there is no difference except packaging