There were a few concerns with the Core i7/Nehalem architecture originally as early reports didn't show favorable gaming performance or overclocking abilities.
This was a big concern considering these were two things that the Core 2 did unlike most other processors in history. The Core 2 Duo processors in particular were notorious for reaching overclocks in excess of 1GHz with very little effort.Furthermore, when they were first introduced, processors such as the Core 2 Duo E6700 were able to blow away high-end Pentium D and Athlon64 X2 processors in games with ease.
There are loads of reports floating around the web that claim the Core i7 processors will be difficult or almost impossible to overclock. Based on what we have found this simply is not true, and if anything the Core i7 processors are just as easy to overclock as the Core 2 processors.
This was made evident throughout our tests that included results for the Core i7 965 Extreme Edition processor (clocked at 3.33GHz by default) running at 3.88GHz without much effort. Given more time and understanding of the platform, we believe 4GHz is a very realistic target.
As time permits and we can test more motherboards using the X58 platform, we will follow up with an article dedicated to overclocking the Core i7 in the coming weeks.