See profile for specs. If I got 512MB of DDR400 to replace my SDRAM and got a new mobo, would my CPU or video card be a bottleneck? I am looking at upgrading, perhaps with a new case like the Antec SX1040 Performance 2 Tower, looks very nice. May get a new CPU around 2.6-3.06Ghz and new speakers and soundcard, Audigy X-Gamer card and Logiteck Z-560 or 580 speakers. We'll see how the budget goes.