You have gotten your money's worth out of the 7478 presario. It's a k6 socket 7 cpu setup. It isn't worth upgrading. By now, the power supply is outdated, and ddr ram is twice as expensive as ddr2. I would keep it for a spare internet pc, and put your $$$ into a new pc with vista, or if you can wait, windows 7. I like windows 7 better than vista. Fatwallet has a listing for a dell vostro 220 with Intel e7400 cpu, 2 gigs of ram, vista basic, and a 23 inch dell monitor for around $410 shipped. It's a good deal; you can add a mid range video card such as the 4650 or 3850, which the dell power supply will easily handle.