History of Processor Speeds

Today's computers depend on performance speed to get us through our multiple applications and programs. The essential piece of machinery that makes this happen is the processor or CPU (Central Processing Unit). The evolution of the processor has equally matched the world's technological advances and our increasing need for speed and reliability.

Stored Data

Mathematicians John Von Neumann, J. Presper Eckert and John Mauchly invented the concept of a computer with stored digital instructions in the 1940s. Until this point, computer programmers had to rewire the circuits in order to get a computer to perform a certain task. These men came up with the concept of a digital computer with processing instructions stored on a memory that had the capacity to logically vary those instructions as needed.

First Microprocessor

In 1971, Busicom contracted a small company in the Silicon Valley to develop an integrated circuit for a business calculator. Little did Busicom know that giving this job to Intel would pave the way for the CPU of today. Intel replaced the arduous task of putting together a custom wired chip with a flexible 4004 microprocessor that worked from instructions stored on a separate Read Only Memory (ROM) chip. Now, rather than building a whole new computer every time someone needed a new strategy, programmers could simply reprogram the ROM, put it in the same computer, and have a whole new format. However, the first processor could only process 4 bits of memory, which meant only 16 possibilities and accessing 640 bits of memory, and that just wasn't enough for long.

Evolution

In 1972, Intel developed the first 8-bit processor that had 16 kilobytes of memory, the 8008. The 8008 followed in 1974 with 64 kilobytes of memory available and an increase in processing by a factor of 10 over the 8008. Then came the 8086 in 1976, a 16-bit processor that was able to handle a full megabyte of RAM (memory). IBM chose the 8088, released in 1979 and quite similar to the 8086, as the processor to use in its first Personal Computer (PC). Intel released the 80286 processor in 1982. It was also a 16-bit CPU, but could handle up to 16 megabytes of RAM. The 286 is the processor that introduced the idea of "protected mode," meaning that a PC could run multiple programs at once without overloading. In the late 80s, Intel released the 80386, a 32-bit processor.

Pentium

In 1993, Intel released its first Pentium processor and began the evolution of processors that really put the company on the map. The first Pentium worked at 60 MHz and could handle 100 Million Instructions Per Second (MIPS). This was soon after followed by the Pentium 2, which operated at 233 to 450 MHz. Intel also released the Celeron processor at this time. The Celeron is a lower end option for the Pentium that, with a smaller cache and slower bus speed (66 MHz compared to the Pentium 2's 100 MHz), was more affordable to users. Bus is the term that indicates how quickly all the components of a computer communicate. The Pentium 3 came out in three versions, operating at 450, 500 and 600 MHz. One of the most recent versions, the Pentium 4, operates at 1900 MHz.

Athlon

While Intel's Pentium processor holds the most brand recognition, a company called AMD has an equivalent, if not better processor on the market as well. The first AMD Athlon was available about the same time that the Pentium 3 came on the market. It was comparable to the 600 MHz Pentium 3, but had dual buses which allowed it to operate at twice the bus speed. AMD also released the Duron, much like Intel's Celeron. It too beat out the Celeron with a bus speed of 200 MHz, compared to Celeron's 66 MHz. With the release of the AMD Athlon XP, AMD decided to stop stating the operating speed in terms of MHz because the company didn't feel it was accurate enough. Comparatively, the Athlon XP supposedly runs at 25 percent higher than Intel's 1900 MHz Pentium 4.

References

• Geeks.com Tech-Tips: Microprocessor History
• PCMech: A CPU History
• InfoPacket: Processor History

Resources

• Processors