That is correct. You CAN mix RAM speeds, but the logic board will dumb the faster speed down to that of the slower speed. PC133 can be used in any G4. Nate -------------- Original message ---------------------- From: C D T <cdt at globaldsl.net> > Someone please nail me if I'm wrong, but I don't think the bus speed is > the limiting factor. Even in a machine that has a faster bus speed and > can use faster memory, the machine can only work at the speed of the > slowest memory module installed. That is why you usually don't mix > speeds. PC133 is generally backward compatible and will function in > PC100 spec'd computers - but at the slower speed. > > Dan >