iXBT LABS has posted an article called Intel Pentium III and Celeron Overclocking: 1.5 Times Faster!. Here a clip:
As you can see, the results are quite curious. Pentium III 500 overclocked to 750MHz nearly catches up with Intel Pentium III 800B working at 133MHz FSB and leaves behind Intel Pentium III 800 with a 100MHz bus. And Intel Pentium III 550 overclocked to 825MHz manages to jump even higher: its performance almost equals that of Intel Pentium III 933. This impressively high performance of the overclocked processors can be explained by the fact that the increase in FSB frequency on i440BX based mainboards leads to the proportional increase in that of the memory. In other words, if you set the FSB to 150MHz, the memory frequency will immediately get equal to 150MHz as well. As for Celeron 566, it shows a bit lower performance, though the increase in its FSB frequency causes a really huge growth: up to 850MHz. According to this benchmark, if overclocked, it performs close to Intel Pentium III 667 with 133MHz FSB and to Intel Pentium III 700 with a 100MHz FSB.Read more
