Intel Core i7 Mobile CPU (Clarksfield) Review

For quite some time now, Intel has been the undisputed leader when it comes to laptop CPU performance. This advantage comes from the fact that Intel has successfully scaled its desktop processor technology for use in the mobile platform. That trend continues with the latest mobile processor platform being unleashed today from Intel: the "Clarksfield"-based Core i7 Mobile processor family and the new PM55 Express Chipset.

This marks the first time that the "Nehalem" Core i7 microarchitecture has been ported over to the mobile side. The fact that the mobile version of Nehalem makes its debut only two weeks following the launch of Intel's Core i5 ("Lynnfield") mainstream desktop CPU and P55 Express chipset is no coincidence. As it turns out, the Core i7 Mobile processor die is identical to the desktop version, but uses mobile packaging--as far as the microarchitecture is concerned, Clarksfield and Lynnfield are essentially the same thing. The lower power demands of Lynnfield (as opposed to the original Nehalem architecture) are in large part what enable it to also be used in notebooks.

What this means is that Core i7 Mobile-based notebooks will see a number of the same benefits that Core i7 desktops already have, such as integrating the memory controller into the processor die, using a three-level cache hierarchy, utilizing Hyper-Threading technology, and taking advantage of Intel Turbo Boost Technology. What Lynnfield/Clarksfield adds to the equation is on-die PCI Express connectivity, getting rid of the Northbridge chip, and improving the Intel Turbo Boost Technology (from the original Nehalem architecture). Additionally, whereas only the previous Intel Core 2 mobile ("Penryn") microarchitecture had primarily dual-core offerings, all of the Core i7 Mobile solutions are quad cores. The three Penryn-based quad-core mobile processors (the 2.53GHz Core 2 Extreme QX9300, 2.26GHz Core 2 Quad Mobile Q9100, and 2.0GHz Core 2 Quad Mobile Q9000) are made from two dual-core chips merged together in a single CPU package, while Clarksfield uses a single-chip (monolithic) design.