I have a Dell Dimension 3000, and I got the lowest memory available (256MB PC3200 DDR non-ECC), knowing that I could get more memory cheaper than from Dell. I know that I can install a 1GB module in one slot or 2 512MB modules. The Dell site says that the best performance comes from adding the 2 512MB modules, but I know that I'm going to want to go up to 2GB later, and I don't want to waste the money on the 2 512s when I know I'm going to end up with 2GB later.
My question is this: How much of a performance hit will I take by doing this? Does anyone have first-hand knowledge of this?