BTW, I think that 566 MHz isn't a stock speed. The bus speed should be 100 or 133 MHz, with this speed you can have a multiplier of 4, 4.5 or 5 (other values are possible for faster P-III) which gives: 400, 450, 500, 533, 600, 666. There has never been a P-III 533 or 666, that leaves 400, 450, 500, 600. If the CPU is running at 566 with a bus of 133 MHz, the multiplier should be 4,2556 (not allowed) or if bus is 100 then 5,66 (also not possible). So unless you already overclocked you FSB I don't understand what is going on here

.