M-line Haswell, turbo to 3.9GHz, 57W TDP
fastest Core i7 for notebooks currently available is the Core i7 3940XM, with four cores working at 3GHz by default and 3.9GHz in its turbo mode. It has a massive 8MB of cache and fits the 55W TDP envelope. It costs an arm, a leg and a few other organs of your choice, as its official price sits at $1096.
As of Q3 2013, the Core i7 3940XM will cease to be the fastest kid on the block. The Haswell replacement is right around the corner and the name of the new market leader is Core i7 4930MX. The “X” stands for Extreme Edition, while M means that the processor comes from the M-line of processors. We mentioned the H-line of processors here
and the only main difference is that H comes GT3 graphics while Intel HD graphics 4600, Intel HD graphics 4x00 for GT2.
The Core i7 4930XM (yes the letters have changed the place from Ivy Bridge MX to XM with Haswell) is a quad-core with eight threads, 3GHz core clock, 3.9GHz maximum single core turbo, 3.8GHz max dual-core turbo and an impressive 3.7GHz max quad-core turbo clock.
The graphics core of choice Intel’s new GT2 HD graphics core, that works between 400 and 1350MHz, but we are not aware of the number of graphics cores inside at this point. The fastest supported memory is rather disappointing, DDR3 or DDR3L 1600, and we expected a higher number here.
The 57W TDP is massive and you can expect to see this absolute performance king only in the biggest notebooks around, as well as in some pricey all-in-ones.