Today, almost each processor can be run faster than the speed it was labeled for. This applies even more if you raise the core voltage a little bit. One problem is of course the increasing chip temperature, so cooling is very, very important. You should always raise the voltage step by step and never go higher than 15% beyond specs. This way it's quite easy to get a faster system without risking the processor.

2.1 or 2.2 V have proved to be reliable for Mendocino CPUs. More can sometimes bring the desired success, but the risk for your CPU increases heavily. To have a Celeron 566 running at 850 MHz, you only have to raise the default voltage of 1.65V to 1.75V. Our Celeron 600 did not want to run stable at 900 MHz, so I recommend keeping below this clock speed. You can try at 1.8 or 1.9V, but the temperature at almost 1 GHz can only be fought successfully by a high end cooling solution (e.g. Kryotech devices)

What Do I Need To Overclock The Celeron?

• Big cooler with a powerful fan
• A motherboard which provides as many system speed settings as possible (particularly between 66 and 100 MHz)
• A motherboard which lets you alter the core voltage

Overclocking Speed

The following table includes all Celerons, clock speeds and useful voltage settings.

* this setting may fail sometimes
** this setting will most likely fail