ok, this may make me sound like a total idiot but: what makes one bit of ram better than another!? i'm building up a gaming rig and have been checking prices and specs for a while now but can't really sort out what makes one better than the other. are there brands like kingston or patriot that last longer or are faster? is a brand like geil terrible? what is cas latency? and one thing that is really tripping me up, if i'm running 8gb of memory is one stick or two sticks a better choice? basically i don't want to buy a *** stick it just needs to be reasonably fast (1600 or higher) and reliable. thanks!