I have a chance to get a Pentium III 600E or 600EB fairly cheap. The 600E runs on a 100MHZ bus while the 600EB runs on a 133MHZ bus. I am install one of these in a Gigabyte GA-6VX7-4X-A. I am leaning towards the 600EB since I get the advantages of a 133MHZ bus. Has anyone found a big difference in performance between the 'E' and 'EB' series PIII?