Overclocking Guide: That's How It Works
Today, overclocking is no secret any more, it has almost become some kind of sport. The definition for overclocking is simple: Overclocking means operating an IC beyond its specified clock speed. No more, no less.
The core speed is the multiplication of the front side bus clock and the multiplier. Most modern processors work at 100 or MHz FSB clock or more, but the Celeron was kept at 66 MHz FSB clock.
Few years ago, you could overclock processors by choosing a higher multiplier. This option was supposedly eliminated in order to fight CPU remarking. Counterfeit processors have regularly appeared in the market (e.g. a Pentium II 266 which was given a new cartridge, labeled at Pentium II 300), as the CPU speed was only defined by your setting. Nowadays, the restriction to only one multiplier is both some kind of overclocking prevention and counterfeit protection.
As you can see, the only way of overclocking today is choosing a higher front side bus clock. Intel specified 66, 100 and 133 MHz, but today's motherboards offer some steps in between those large increments. 75 and 83 MHz are very widespread today. Celeron overclocking requires many small increments between 83 and 100 MHz, as most Celerons run perfectly at 83, but fail at 100 MHz FSB. We benchmarked at 92 MHz as well, as this clock speeds closes the logical gap between 83 and 100 MHz.
In case your board should offer 1 MHz-increments (Abit BE6-II, BF6, BX133-RAID, Epox BX7+ and others), you have the chance to find out the maximum clock speed by slowly closing in on the final limit MHz for MHz. Of course this cannot be done in an hour, but you will have to spend one or two days just playing with different clock speed settings. In the end you should have your Celeron running at the highest possible core speed.