Ram is still dirt cheap these days. If you have an intel chip, ram speed really doesn't matter since the ram controller is on the CPU itself now, so get the largest sticks you can find and don't worry too much about the speed of the ram. You'll want to make sure that at least the two primary channels are filled. If you have an AMD processor ram speed is a little more important, but capacity is still king for most things. Generally even for gaming you aren't going to really notice more than 12GB ram unless you have truly outstanding video cards in the system and a beefy processor and a SSD