754, 939, AM2, AM2+, AM3: Sorting AMD's Sockets
How To Confuse Your Customers & Kill Your Stock Price
Way back in the prehistoric era, AMD aficionados were absolutely giddy about the new and exciting cutting-edge capabilities that the new Socket 754 would give over the dated Socket A, also known as Socket 462. With 292 more pins to allow for a wide variety of new features, it was true that AMD's Golden Age was in full bloom, and that the new Athlon XP series of processors would establish AMD once and for all as the reigning king of CPUs.
To those who are still wondering what a socket is, it's the place on the motherboard where the CPU, or brains, of the computer plugs in. The back of the CPU has lots of little pins each fitting in its own tiny socket. Generally, (but hardly always) the more pins the CPU/socket has, the more capable the processing performance is.
Socket 754 did live up to all the hype. With HyperTransport connecting the CPU and the north bridge, a 16 bit (two byte) DDR (double data rate) bus, and its allowance for a bandwidth of 1.6 GB/s, it seemed like AMD had left Intel in the dust once again.
No sooner had AMD fans everywhere adopted the 754 platform as their very own, and were envied with reason by many Intel side 775 socket owners, AMD decided to jump sockets again, this time to Socket 939. The extra 185 pins allowed for a cornucopia of engineering wonders including allowance for DDR SDRAM memory with 6.4 GB/s memory bandwidth; 3DNow!, SSE2, and SSE3 instruction set support and a single HyperTransport link of 16 bit capable of 2000 MT/s. 939 allowed for CPUs to benefit from 64KB Level 1 caches, and either 512KB or 1 MB Level 2 caches.
So strong was the "cache"-t of the 939 platform that some 754 motherboards were equipped with a slot for a 939 daughterboard for easy upgrading. To say that AMD had a winner in 939 was an understatement. Intel, a company at least ten times larger than AMD, was on the ropes with its plunky Pentium 4 series featuring the atrocious engineering hash called Prescott, a CPU that ran hotter than a steel smelter and sucked electricity faster than a warehouse full of hairdryers. (I could have said that it sucked more than a warehouse full of Hoovers, but this is a family Hub.) :)
We've all seen the Rocky movies when our hero is on the ropes, bloodied, beaten, hallucinating about his homely Coppola-related wife and then manages the strength for a punch that lays out his fiercer, younger, monstrous opponent out like a wet rug being thrown out of a flooded house. That's pretty well what Intel did. After doubling up their reprehensible CPUs to premiere the Pentium D series which set new lows for abominable, odious, contemptible and generally all-round vile heat, power consumption and general deficiency on their Socket 775 platform, Big Blue landed a punch named Conroe on AMD's jaw and the Green Machine never really recovered.
Conroe was the code name for Core 2 Duo (amazing chip, idiotic name) which was the first dual core processor to break all the rules and achieve performance far above those of mortal Athlons. Overnight, AMD's dual cores were relegated to the bargain basement bin, many fetching less than $100 which was a price cut of over $600 for some models. It was like driving out of your local Honda dealer with a brand new Civic you just paid $3,000 for.
AMD could not compete on speed. They could not compete on performance. They could only compete by slashing prices. Their top end dual core was getting eaten alive by a mid range Core 2 Duo, and then to rub salt in the wounds, Intel introduced the quad core models to bring close to supercomputing performance to the desktop.
AMD had to fight back, but how? They introduced the AM2 socket. The AM2 socket had... er... one... extra pin and was essentially a rehash of their server side Socket 940. The hype surrounding AM2 was that it would speed up CPU operations so much that Intel would have to grab its Core 2s and run back to the cave where it dwelled for most of this decade.
When the first AM2 systems landed in the hands of independent testers the truth came out. AnandTech measured the performance advantage over an otherwise identical 939 at a whopping 2%. Wet rug, outdoor of flooded house. Thud.
Even some of the rabid AMD fanbois by now were ready to either go Blue or jump off the nearest skyscraper. AMD realized that they had to do something, so they immediately launched AM2+. What does AM2+ do? Well, it has HyperTransport 3.0! And a nice plus sign after the name!
AM2+ was shunned like an outbreak of bird flu in Indonesia. Few people could actually see what the heck the difference was with AM2, and they were right. By this time the PR nightmare had reached such levels that AMD had to pull out all the stops and announce... Socket AM3! To the chorus of groans from the gathered multitude, this third socket in nine months was to use DDR3 RAM, which is was plagued by latency and other issues, and generally isn't worth the extra cost.
Let's please not even bring up Socket F which is a 1207 pin design used only in the dual socket Quad FX platform that even the most fanatic AMD evangelists refused to buy.
What was next for AMD? Many observers doubted that they will be able to survive long in their state. They turned the acquisition of Canadian video card manufacturer ATI into a conflagration, their stock was devalued over 70%, and they missed deadline after deadline in attempting to release their long-awaited Barcelona/Agena/Kuma series of alleged Core 2 Duo-killers.
AMD is a prime example of the marathon runner who arrives within a few hundred yards of the finish line leading by two minutes and decides to go off and have a rest and an ice cold lemonade. The extent to which AMD dropped the ball and confused and alienated the most smitten AMD fan may have few equals in American corporate history.