4 -- Intel's new Core i7-3960X processor, code-named Sandy Bridge-E, has been touted as the fastest desktop processor ever.
Since the Gulftown and Sandy Bridge-E are both 32nm six-core, 12-thread processors, it's clear that there are some architectural changes in the Sandy Bridge generation that are improving performance, particularly in things that are very heavily multithreaded, such as Monte Carlo simulations.
Source: Sandy Bridge-E Proves PCs Are, In Fact, Getting Faster
20 -- This week, Intel started shipping its second-generation six-core desktop CPU, known as the Sandy Bridge-E. Every review I've seen points to this being the fastest desktop chip ever.
The Sandy Bridge-E chips are big, measuring 435 mm2 with 2.27 billion transistors, manufactured on a 32nm process.
In any case, the Sandy Bridge-E chips are likely to be the top end of the desktop space for the next year or so.