It was the first Intel Celeron processors clocked at 266MHz that took the overclocking world to new levels. In the past, being able to attain a 50% increase in clock speed through overclocking was unheard of; however the maturing of Intel’s manufacturing processes as well as the deliberately low clocking of the Celeron parts resulted in a performance gold mine for enthusiasts.
Unfortunately it is only the first iteration of a new Celeron core that actually promises this sort of overclocking potential. In order to understand why, you have to understand the Intel methodology for applying a single microprocessor architecture to multiple market segments. Let’s take the Celeron in particular; once a higher end desktop core has been in production for a significant amount of time and yields have reached a certain level, Intel readies the core for use in the Celeron line. The core isn’t simply branded as a Celeron without any modifications, generally speaking Intel performs one or more of the following alterations to the core:
– Lower L2 cache size/speed
– Lower core clock speed
– Lower FSB frequency
The beauty of this method for overclockers however is that in the event that Intel limits the core by reducing its clock and/or FSB frequency then the chips are almost guaranteed overclockers to higher levels. For example, when the first Celeron 266MHz processors hit the streets they could easily overclock to 400MHz just by increasing the FSB frequency from 66MHz to the 100MHz frequency of their Pentium II counterparts. Since the cores were relatively similar, it wasn’t asking too much of the Celerons to run at the higher clock speed.
While we don’t normally cover Intel’s Celeron line, whenever there’s an introduction of a new Celeron core we’re here to exploit it’s overclockability. Today Intel is introducing the first Celeron processors based on a Pentium 4-derived core on a 0.18-micron manufacturing process. The use of the 0.18-micron manufacturing process is a bit puzzling (you’ll understand why later) but the end result is that an overclocked Celeron could easily become a poor man’s Pentium 4.
Let’s find out a bit more about the architecture of the chip before diving into a performance investigation, shall we?