Hi Diane, My husband did a little research into this issue for our old G4 and he was told that if you replace all the chips with faster ones, the machine will run better. But if one or more slower chips are mixed in with the faster ones, the processor will adjust to the speed of the slower chip. His suggestion is to go for the faster chip if they aren't that much more. Hope this helps, R. S. Williams On Saturday, January 4, 2003, at 11:09 AM, diane wrote: > Thanks, but that's not even close to the question I had asked. <G> > > I was wondering if it was worth spending the little extra on 133 DIMMS > when my G4 really only needs 100s > > > Diane > > >> I go to Data Memory Systems for RAM. Their stuff is very reasonably >> priced >> (competitive) and the proper type for your model computer. Also, it's >> guaranteed to work or they replace it immediately. > >