Efficiency Explored: What's The Perfect Clock Rate For Your Core i5?

Core i5-750: Best Choice?

Our Core i5/i7 coverage for the LGA 1156 platform has already been comprehensive:

Core i5 And Core i7: Intel’s Mainstream Magnum Opus

How Does Lynnfield’s On-Die PCI Express Affect Gaming?

Core i5/i7 Efficiency: A First Breakdown

Intel’s Core i5 Overclocked

The entry-level model in the Lynnfield lineup, Intel's Core i5-750 at 2.66 GHz, anchored our overclocking article, and we liked it well enough to keep using it for our efficiency analysis. This processor starts at $196 and offers better efficiency and higher peak performance than the Core 2 Quad, despite its relatively low base clock speed of 2.66 GHz. Thanks to Intel’s second-generation Turbo Boost feature, the chip will accelerate its core clock speed by up to four clock speed increments (referred to as bins, and offered in 133 MHz increments) if only one or two cores are used. Effectively, this has the processor running at 3.2 GHz. If three or four cores remain active, it still can increase overall clock speed from 2.66 to 2.80 GHz.

If we’d used the Core i7-870, which is currently the top LGA 1156 model, the maximum clock speed would already be 3.6 GHz. Obviously, the headroom for overclocking is a bit smaller and the processor cost much more significant at $562.