In November 2008, Intel introduced the Core i7 LGA 1366 processors, the first CPUs based on its new Nehalem architecture. After rolling them out on Socket LGA 1156 in September 2009, Nehalem was then released on 32nm dual core and six core CPUs in January and March 2010. After more than two years of loyal service, Nehalem is now being replaced by Sandy Bridge.
The Sandy Bridge architecture
Sandy Bridge is the code name given by Intel to its new architecture and the processors built around it. This new generation is a ‘tock’ in Intel parlance, signifying a new architecture using a fabrication process already used previously. Sandy Bridge CPUs are therefore manufactured on the 32nm process, like the Westmeres, the 32nm versions of Nehalem. The quadcore version is based on a 216mm² die with 995 million transistors, against 296mm² and 774 millions transistors for a 45nm Lynnfield LGA1156 quadcore.
Among the innovations introduced by Sandy Bridge CPUs, the most notable are:
- A new Socket LGA 1155
- An integrated IGP sharing the L3 cache, now known as LLC (Last Level Cache)
- An improvement to the IPC and performance per watt
- A new AVX (Advanced Vector Extension) instruction set
- A new version of Turbo Boost
Beyond these aspects of the spec on which Sandy Bridge differs from its predecessor, the technological choices introduced or reintroduced with Nehalem have been retained, namely:
- The integrated DDR3 memory controller (dual channel and DDR3-1333)
- The built-in PCI-Express controller (2 x 8 PCI-E 2.0)
- A three levels cache architecture
The first Sandy Bridge models will be on the market this quarter. There will be no less than 29 models, desktop and mobile together, either dual or quad core. Only the quad core models will be available as of January 9 and we’ll have to wait until February 20 to see the dual core versions. The release of these processors has been accompanied by ten new chipset models that can support them, including the P67s and H67s, code name “Cougar Point”.