As mentioned previously, the Slot-1 Celeron CPUs are indeed clock multiplier locked, yet FSB speed unlocked. This means that as long as the user chooses the 366's 5.5x multiplier setting, they can select and experiment with any of the available bus speeds that their mainboard offers.
Here's a look at all of the "possible" overclocking combinations that the Celeron 366 could see on an Abit BH6 mainboard
Stock: 5.5 x 66MHz = 366MHz
5.5 x 75MHz = 413MHz
5.5 x 83MHz = 456MHz
5.5 x 100MHz = 550MHz
5.5 x 103MHz = 567MHz
5.5 x 112MHz = 616MHz*
5.5 x 124MHz = 682MHz*
5.5 x 133MHz = 732MHz*
*Virtually impossible to achieve
That's certainly a lot of options when it comes to overclocking, but unless you own a company named "Kryotech" (link to K62-500 Review) then you're not going to be able to even sniff the 616, 682, or 732MHz clock speeds.
