|
Page 1 of 5 Introduction
Arguably one of the fastest advancing components of computer technology, the CPU has leaped to extraordinary levels on both workstation and desktop platforms alike. In the span of 20 or so years, the CPU has made such incredible changes; that it would be hard to imagine what they will be like in another 10 years. 500GHz anybody?
When you say CPU today, the first thing that pops into the heads of an average computer user is Intel or AMD. There are more than just those two companies though. In fact, one company; Cyrix has just released a new - but somewhat disappointing - processor: the Cyrix III. A recently formed company, Transmeta, has released an x86 compatible processor called Crusoe for portable devices.
Going back to the old school days, before the real boom of computer popularity, many other companies were developing their own processors. Both Motorola and Sun had their own flavors of CPU, going by the name 68000 for Motorola (which were used in the early Macintosh systems) and SunSPARC for Sun. However, this article deals with the history of x86, and more specifically, the product history of Intel, AMD, and Cyrix.
Intel and x86
The start of the modern CPU boom we're still seeing today is hard to put a finger on. I believe the start was at the release of the 8086, which sported a 16-bit internal design and external bus that allowed it to work in 16-bit mode everywhere. The 8086 blasted away at amazing speeds of 4.77 and eventually 8 MHz -- hardly a calculator by today's standards. All this started in 1978.
Late 1978: Just a short while later, Intel released the 8088. This processor also came in 4.77 and 8MHz flavors, and was used in many of the early IBM PC computers as it was cheap(er) to produce and of course, featured the stunning 16-bit internal design. The 8088 used an 8-bit external bus, however, because IBM didn't want the PC being faster than its mainframe systems. An 8-bit external bus also allowed IBM to use off-the-shelf components to make the system, resulting in higher market priority.
 I wonder if an 8088 is worth more today than it was then. Not likely.
Next in line was the 80186 which wasn't very impressive or known, as the chip was buggy and there was little improvement over the 8088 except for an external 16 bit bus. It wasn't a popular processor and was passed over by most manufacturers. The big guns hit with the 286... Intel's 286
The Intel 80286 was released in 1982 and is commonly referred to as simply the 286. The 286 came in 8, 10, and 12 MHz flavors, sported a full 16-bit architecture. It also had a new feature: protected mode, which allowed multiple programs to run using the same memory without fear of crashes. Unfortunately, once in Protected Mode, you were stuck there, earning the 286 the name 'brain dead'.
The 386
1985: Now, here's where the good stuff comes about. Intel's 80386, or 386, featured powerful 32-bit architecture and built-in multitasking and memory management units. The 386 came in whopping 16, 20, 25 and 33 MHz speeds. The 386's Virtual Mode allowed it to create Virtual x86 machines which each program had, and share processor cycles between them. Of course, this required more advanced operating systems like OS/2 and Windows 95 to take full advantage of it. It's too bad that running Windows 95 on a 386 would be a more painful process than getting your teeth yanked by a 400 pound gorilla wielding an ice pick. Windows 3.1 really didn't care for all that fancy multitasking hoopla.
 DX-25: Now THAT is power!
The 486!
Released just before 1990, the 80486, or 486 came in two flavors: a DX and an SX model. The DX model featured for the first time, an on-board FPU (Floating Point Unit) that eliminated the need for the purchase of a separate math co-processor. The 486 featured another first in x86 history: Onboard cache! The original 486DX came in speeds of 25, 33 (I had one of these!) and 50MHz. The 486 was a huge hit with consumers and can almost be credited with a boom in PC sales. The later released DX2 and DX4 versions of the 486 doubled and tripled the bus speed. These varied in speed as the board speed varied. These were indeed nice processors and power houses in their own right. The 486DX4 maxed out at 100 MHz.
|
