Intel gave a go ahead for the media to publish reviews of its brand new dual-core processors under the Core i5 6xx and Core i5 6x1 series. The processors are based on the new "Clarkdale" processor die, and make use of the company's 32 nm next generation HKMG manufacturing process. Unlike conventional processor packages based on the Nehalem/Westmere architecture, the new processors move the northbridge component of the system onto the processor package, only that it is based on a separate 45 nm die within the package. The 32 nm processor die houses two processor cores along with up to 4 MB of L3 cache, while it is wired to a larger iGPU die which houses the dual-channel DDR3 memory controller, a graphics core, PCI-Express root complex, along with other components traditionally found on northbridge chips.
The first three models in the new Core i5 series are the 3.20 GHz Core i5 650, 3.33 GHz Core i5 660 and 661 (latter has a faster iGPU), and 3.46 GHz Core i5 670. These processors have the LGA-1156 package and are compatible with existing P55 Express chipset (albeit without the iGPU feature), along with the company's new H55 Express and H57 Express chipsets that support the Flexible Display Interface that provides connectivity to the processors' iGPUs. The new processors feature HyperThreading Technology, with which it provides the operating system with four logical CPUs (threads) to deal with, TurboBoost technology which powers down a core and overclocks the other when the task load is low.