I've heard that celeron's are "clock-locked"....is this true?

[TerminatorM101]

I've heard that celerons are clock-locked and when I switched the jumpers on my celeron 300 to jump it to 333 and nothing happened I guessed that it was true...how do you unlock your clock-speed?

[Eli]

Actually they're multiplier locked. To overclock them you need to raise the bus speed, which is 66MHz by default. Unlocking the multiplier is not an option I'm afraid.

[TerminatorM101]

so how to you raise the bus speed?

[krusty the klown]

The bus speed (FSB speed) is raised either by changing jumpers on the mobo, or through BIOS SoftMenu settings (sometimes a combination of both). 'Home brew' boards (frequently used in brand name PCs) tend to either have limited options, or will just automatically detect the default speed, whereas separate 'off the shelf' mobos used in DIY systems tend to be more OC friendly.

The celeron 300a was probably the first real OCing gem. Its default settings were 4.5 * 66MHz (multiplier and FSB). Many people ran them at 4.5 * 100MHz to give 450MHz clock speed. Leave the multiplier alone as it's locked and find out if you can raise the FSB - your mobo manual should have details in the CPU installation instructions.