Intel Core i7 920 and 940 CPU review
 

Away from the actual CPU cores is where much of the real interest lies, in what Intel prefers to call the "uncore" - Basically everything that isn't the CPU cores themselves. The most notable change within this "uncore" is probably the addition of a memory controller on the CPU die, moving it from the motherboard's northbridge as per AMD's designs since the Athlon 64. This memory controller supports DDR3 at speeds of up to 1066MHz in standard Core i7 parts, and up to 2000MHz on Extreme Edition CPUs, while all Core i7s have a triple-channel memory controller - A step up from the dual-channel controller that has been commonplace ever since the introduction of DDR memory, which gives the CPU more bandwidth to play with (25.6 GB/second with 1066MHz memory) as long as the system's memory is fitted in banks of three modules. As per AMD's on-board memory controller, Intel's use of a similar design removes an extra "hop" for the CPU when accessing system memory, which reduces latenc y quite considerably.

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