The Big Processor Guide - Notes
Consider this the caboose of the guide. Not really critical, and it comes last, but it has its uses.
Much ado is made about how bus speeds should be measured. Specifically, the Front Side Bus. Go read the Talk pages of some Wikipedia articles on processors (I read more than a few preparing this), and you'll see what a fight it can be. Fundamentally, it's all a matter of multiplication.
Old buses like those used on the 486 and its predecessors operate at the same frequency as the clock signal driving them. They trigger on either the rising or falling edge of the square wave provided by the clock.
Some AMD processors (principally on Socket A) engage it what is known as "double-pumping". In essence, they operate at double the frequency of the clock's signal. They trigger on both the rising and the falling edge.
Some Intel processors (beginning with the Pentium 4) engage in what is known as quad-pumping. They operate at four times the frequency of the clock signal. They trigger on the rising and falling edges, but also the peak and trough of the clock signal.
And then there's HyperTransport. HyperTransport is a high-speed link technology. AMD's K8 series use HyperTransport as their link to the rest of the system, and have an integrated memory controller that communicates with the CPU over HyperTransport. HyperTransport utilizes double-pumping. It allows much faster communication between the processor and memory controller- and traditionally, this is a major aspect of how Front Side Bus is defined.
A number of solutions have been proposed to this problem. One is to rate buses in terms of how many transfers per second they can support (often measured in MT/s). This divorces the result from raw operating frequency, but is also confusing to many users. Another is to list the clock frequency and then note any special properties of the bus. That is what I have elected to do.
So simply for the record: AMD's HyperTranpsort bus operates at 200 MHz, and is double-pumped.
This all becomes more complex when you consider Intel's future Common System Interface. It is in many ways similar to HyperTranpsort.
I also would like to thank those that directly helped make this guide possible. To the beta testers, who mercilessly hunted down errors; to Justin, who helped with code-ish things; and of course to Rose (dear Rose), the school that destroyed the part of my brain that should have told me an undertaking of this size was a bad idea. And now, links:
- Chris Hare's pages, which provide information on most processors, and some information on GPUs
- The Red Hill Guide, which covers the history of CPUs and other hardware
- Chip Geek
- Anandtech on some codenames
- Anandtech article on AMD's Sockets AM2, F, S1
- Anandtech list of "shipping" AMD processors
- Tom's Hardware interactive CPU comparison
- Tom's history of AMD
- Madshrimps information on HyperTransport and related
- CPU Planet's detailing of Intel and AMD cores (old, but still interesting)
- Details on AMD's manufacturing process
- Wikipedia List of AMD processors
- Athlon 64 power consumption comparison (focus on Venice)
- Information on the Sempron Paris
- First generation of Socket 939 processors
- AMD Athlon 64 Core Explanation
- CoolTechZone::Intel: The Art of Naming Processors
- Desktop Processor Quick Reference Guide
- The Quickest Guide to AMD Processors...Ever. - Guide - Short-Media
- Intel announces major 2006/2007 roadmap changes
- Tom's: Intel Moves From Dual Core To Double Core - 65 nm Intel Double Core Preslers Forward
- Buying Intel desktop CPUs is now a numbers game (Intel model numbers, at their introduction)
- Tom's Hardware's big table of processors
- Intel® Processor Numbers
- The Mother of All CPU Charts 2005/2006 | Tom's Hardware
- Intel® Laptop Processors Product List
- Intel® Desktop Processors Product List
- Intel® Server and Workstation Processors Product List
- CPU-World: CPU families
- PCGuide - Ref - Processor Families
- cpu-collection.de >> by Manufacturer
- Intel mobile processor comparison
- AMD TurionT 64 Full model listing
- Mobile AMD SempronT Processor Product Comparison
- Mobile AthlonT 64 model number comparison
- CPU-World: AMD Mobile Duron 1200 - DHM1200AQQ1B
- List of AMD Athlon 64 microprocessors - Wikipedia, the free encyclopedia
- Naming: Fab51: AMD 64 OPN reference guide
- Intel Core announcement
- AMD dual-core demo (Flash)
- AMD Multicore presentation