Those of us who are conversant with technology are more or less conditioned to accept and even expect change as a natural part of the course of things. New gadgets and gizmos debut regularly, each one offering some set of advantages or refinements over the prior generation. As a result, well, you folks are a rather difficult lot to impress, frankly speaking. But today is a day when one should sit up and take notice. I've been reviewing processors for nearly ten years now, and the Core i7 processors we're examining here represent one of the most consequential shifts in the industry during that entire span.
Intel, as you know, has been leading its smaller rival AMD in the performance sweeps for some time now, with a virtually unbroken lead since the debut of the first Core 2 processors more than two years ago. Even so, AMD has retained a theoretical (and sometimes practical) advantage in terms of basic system architecture throughout that time, thanks to the changes it introduced with its original K8 (Athlon 64 and Opteron) processors five years back. Those changes included the integration of the memory controller onto the CPU die, the elimination of the front-side bus, and its replacement with a fast, narrow chip-to-chip interconnect known as HyperTransport. This system architecture has served AMD quite well, particularly in multi-socket servers, where the Opteron became a formidable player in very short order and has retained a foothold even with AMD's recent struggles.
Now, Intel aims to rob AMD of that advantage by introducing a new system architecture of its own, one that mirror's AMD's in key respects but is intended to be newer, faster, and better. At the heart of this project is a new microprocessor, code-named Nehalem during its development and now officially christened as the Core i7.
Yeah, I dunno about the name, either. Let's just roll with it.
The Core i7 design is based on current Core 2 processors but has been widely revised, from its front end to its memory and I/O interfaces and nearly everywhere in between. The Core i7 integrates four cores into a single chip, brings the memory controller onboard, and introduces a low-latency point-to-point interconnect called QuickPath to replace the front-side bus. Intel has modified the chip to take advantage of this new system infrastructure, tweaking it throughout to accommodate the increased flow of data and instructions through its four cores. The memory subsystem and cache hierarchy have been redesigned, and simultaneous multithreading—better known by its marketing name, Hyper-Threading—makes its return, as well. The end result blurs the line between an evolutionary new product and a revolutionary one, with vastly more bandwidth and performance potential than we've ever seen in a single CPU socket.
