How to Overclock an Intel Celeron Processor

A small pile of socket 370 Celeron CPUs

Overclocking the processor has long been a way of getting the performance of a faster and more expensive processor without spending the extra money. The Celeron processor was introduced by Intel to market their own budget desktop CPU to battle alternatives from AMD, Cyrix, and IDT. Overclocking history was made with the Celeron CPU (Central Processing Unit) in 1998 when it was found that a lowly 366MHz (megahertz) Celeron was easily overclocked to 550Mhz, and was capable of SMP (Symmetric Multi Processing), allowing the home user to build a very fast and very powerful dual CPU desktop system for the cost of a single (and technically superior).

Instructions

1. Turn your computer on, and enter the BIOS (Basic Input/Output System). On most PCs this is done by pressing the "Del" when the computer is first powering up, but it may also be "F2," "F10," or another key. Check your motherboard documentation if you are not sure.

2. Navigate to the page with the CPU settings on it. Depending on the motherboard this may be labeled "Advanced Settings," or "CPU/FSB Settings," or something else entirely. Again, consult your documentation if you are not sure.

3. Locate the setting for the CPU "FSB" or "Front Side Bus." To overclock the CPU, raise the speed of the FSB. For instance, using the example of the Celeron 366A in the Intro, the CPU was meant to use a 66MHz FSB, but when set to a 100MHz FSB, the CPU went from running at 366MHz to running at 550MHz. CPUs are multiplier locked, which means you cannot adjust the FSB multiplier anymore, so the only way to overclock it is to increase the FSB speed.

4. Test for system stability after each FSB increase. Make sure Windows boots up completely and without issues. Run some applications; games are specifically good ways to test system stability after an overclock. If Windows cannot finish booting or does not boot at all, or even worse the system does not POST (Power On Self Test), then drop the FSB and try for a smaller overclock.

Tips & Warnings

• Increasing the FSB by 5MHz at a time is a slow, but relatively safe way to overclock. Trying to overclock by a large number at a time is more likely to damage the CPU.

• Use a good quality heatsink and fan, as well as a good quality thermal compound. Overclocking produces more heat, so to run stable, the CPU needs to stay cooled.

• Overclocking is not a given, and will void your CPU warranty. It can also decrease the lifetime of the CPU, slowly degrading it over time. It is not uncommon for an overclocked CPU to no longer function even at stock speeds after a year or more of running overclocked.

References

• William Bellisle-Pio; Network Systems Administrator; Auburn, Washington
• Firingsquad: Dual Celeron 366 Overclocking