Intel now has so many different processor series to choose from it makes buying the right one a difficult job. The current LGA775 platform supports a number of processors featuring different clock speeds, front side bus speeds, cache and cores. The common choice at the moment is the Pentium 4 5xx, 6xx, D series and now the Core 2 Duo/Extreme series of processors. Personally, whenever I purchase an Intel processor for gaming or general use, a processor from the 6xx series is my first choice. The main reason for this is these processors feature a 2MB L2-Cache, where as the 5xx series only offers a 1MB L2-Cache. Another positive attribute of the 6xx series processors is their overclocking abilities.

However, while the price of current Pentium processors is dropping rapidly, the Pentium 4 670 still retails for a little over $600 US. Given the Core 2 Duo E6700 is said to be introduced at $530 US, the Pentium 4 670 is a very unattractive option, especially since the E6700 is significantly faster. However, if you were to hold off and purchase a 4MB L2 Cache Core 2 Duo processor, being either the E6600 or E6700, what kind of overclocking performance could you expect using an affordable after market air-cooled heatsink? Well thats what we are here to find out today and although these are early overclocking results, I have found them to be quite impressive nonetheless.

Today the demand for products that overclock well is extremely high. Many of the computer industries most popular hardware has become so popular due to its overclocking abilities. Even certain processors from both AMD and Intel have become sort after items due to their overclocking abilities. Another perfect example of overclocking popularity comes from the memory market. There are several companies currently competing to produce the most highly overclockable memory modules available. So with overclocking becoming so popular even with the manufacturers, you would assume everyone was doing it.

While the clock multiplier is unlocked on the horribly expensive Core 2 Extreme X6800 processor, it is unfortunately locked on all Core 2 Duo processors. This means the Core 2 Duo E6700 is limited to a x10 clock multiplier and when operating on the 266MHz (1066MHz QP) FSB works at 2.66GHz. However, with reasonably limited cooling in place, I was able to easily achieve a 3.66GHz overclock without compromising stability in the slightest. Some might say big deal, as speeds in excess of 4GHz have been reported. However, like most of my other overclocking articles, I want to see what the processor can do right out of the box.

Of course this means without requiring a cooling system worth twice that of the processor. Cooling systems that could freeze an ice block over the processor in seconds are nice, but for most they are also very impractical. So, while a 5GHz Conroe overclock does sound like fun, this is more of a realistic article that will give you an idea of what can certainly be expected right out of the box. Using nothing more than a Core 2 Duo E6700 processor with the Thermalright XP-120 heatsink, an ASUS P5W DH Deluxe motherboard and some Corsair PC8500 memory, the 3.66GHz overclock came all too easy.

So easy in fact, that I was able to boot up at 3.9GHz, though the system was very unstable. Even at 3.8GHz stability was still an issue with the XP-120, though I was able to run a few benchmarks. For a while 3.7GHz seemed to be the sweet spot, though after long periods of stress testing the system would often come unstuck. Backing the frequency down to 3.66GHz did the trick, as this 1GHz overclock was able to drastically boost performance without compromising stability. Therefore, I believe it is safe to say anyone purchasing a Core 2 Duo E6700 processor can expect to hit at least 3.66GHz when overclocking and here are the results...