What's the difference between: a single 1GB DDR800 RAM card or, 1GB (2x512MB) DDR800 cards running in dual channel? At first, I think that having 2 512 MB would run smoother, but then I want to eventually have 4GB of memory. Perhaps I should get a 1GB stick and wait until next paycheck to get another 1GB stick? Then again, money is very tight, so i'm stuck. I think that my best bet would be 2GB (2x1GB) RAM is best, but that's only my opinion.