In my opinion your system will get the best overall speed increase in adding mem. Your max is 2Gb, 2 x 1GB sticks. The MB installed has a FSB of 533 and is a Socket 478. So any 478 socket processor will work. If you replace the processor with a NON celeron yes you will see an increase but your will have a bottle neck with a FSB of 533. The celeron processors have a very small cache, when you go to a non celeron your increasing your cache on the processor but have done nothing to assist the movement of the data on the MB itself. In easy terms its like a traffic jam, you have cars that would flow nicely on a 4 lane hgwy, but only have 2 lanes available, Traffic Jam.
Money best spent on max out of the memory the system will take. This MB also only supports PC2700 mem. There is nothing you can do to this system what will really show a true performance increase that is noticeable.
TD
