"Champ", I have a dual 533 MHz DA that has been extensively upgraded, and the things that have helped the most in terms of bang for the buck are: 1.) Max the RAM 2.) A better video card. I'm using a flashed PC/AGP GeForce 6200 that works great. After I installed it, the machine seemed to run three times faster, especially while browsing. 3.) A SATA card and drive. Mine is an Acard from OWC, and right now, after all the above, I have lost the urge to upgrade the processor. But mine is a dual 533, and not a single 400. The internal IDE controller really does slow down the system. I'm not sure how much good the processor would do without addressing some of these other bottlenecks. Anyone else out there have another experience? - Michael B. in Cincinnati