A Deeper Look Into Processor

You have already seen how the PC processes and moves data. For most people, the great mystery of the PC is what takes place inside its circuitry. How can this box of chips, wires, and other parts-most of which don't even move -do its work?

A processor's performance -even its capability to function--is dictated by its internal design or architecture. A chip's architecture determines where its parts are located and connected, how it connects with other parts of the computer, and much more. It also determines the path that electricity (in the form of moving electrons) takes as it moves through the processor, turning its transistors on and off. There are many different chip architectures in use today, and each family of PC processors is based on its own architecture. In fact, processors are differentiated by their architecture. 

The processors of IBM PCs and Macintosh computers have such different architectures, for example, that they cannot even run the same software; operating systems and programs must be written to run on each processor's specific architecture, to meet its requirements. A processor's architecture determines how many transistors it has, and therefore the processor's power. Simply stated the more transistors in a processor, the more powerful it is. 

The earliest microprocessors had a few thousand transistors, The processors in today's PCs contain tens of millions. In the most powerful workstation and server computers, a processor may contain hundreds of millions of transistors. When a computer is configured to multiple processors, multi-billions of transistors. A processor includes other features that affect its performance.

Yor example, a processor's performance is by the number of bits of data that can process anyone anime, Currently, nearly all standard PC processors move data in 32-bit

they are called "32-bit processors," In 2003 American Micro Devicen (AMD) released a new generation of desktop PC processors that can handle 64 bits of data, (High-end workstations and many mini-computer systems have used 64-bit processors for about a decade. )

Microcomputer Processors

For two decades after the birth of the personal computer, the biggest player in the PC CPU market was Intel Corporation. This dominance began to change in 1998 when several leading computer makers began offering lower-priced systems using chips made by AMD and other chip manufacturers. Initially, these microprocessors offered less performance at a lower price. That situation has changed, however, as AMD made rapid advances in its products' capabilities. Today, Intel and AMD chips compete for head to head, not only in performance but also in price. Intel and AMD are not the only manufacturers on the block. Motorola, now known as Freescale, manufactured the processors for all Macintosh computers up to and including the G4. They still make chips for communication devices. The newer Macintosh G.S boasts a chip made by IBM. Many other companies make specialized processors for workstations, minicomputers, handheld devices, automobile electronics, and kitchen appliances.

As you read the following sections, remember that performance specifications and features can change rapidly. Chip manufacturers make constant improvements to their products; as a result, the most popular PC processors now operate at speeds higher than 3 GHz, and they continue to be faster every month. By continuously refining chip designs and manufacturing processes, chipmakers are always finding ways to add more transistors to chips.

Intel Processors

Intel is historically the leading provider of chips for PCs. In 1971, Intel invented the microprocessor--the so-called computer on a chip--with the 4004 model. This invention led to the first microcomputers that began appearing in 1975. Even so, Intel's success in this market was not guaranteed until 1981 when IBM released the first IBM PC, which was based on an Intel microprocessor.

Advanced Micro Devices (AMD) Processors

In 1998, Advanced Micro Devices (AMD) emerged as a primary competitor to Intel's dominance in the IBM-compatible PC market. Until that time, AMD processors were typically found in lower-performance, low-priced home and small business computers selling for less than $1, 000. With the release of the K6 and Athlon processor series, AMD proved that it could compete for a feature with many of Intel's best-selling products. AMD even began a new race for the fastest PC processor.

Freescale Processors

Freescale Semiconductor, Inc., a subsidiary of Motorola, Inc., has a 50-year history in microelectronics. As mentioned earlier, many Apple computers use Fre-processors. Freescale processors were also an early favorite among companies that built larger, UNIX-based computers. Through the years, Freescale offered two processor architectures that were used in Macintosh computers. The first is known as the 680x0 family. A new type of processor, which was developed by Freescale, Apple, and IBM, has replaced this family of processors. This new processor architecture, called the PowerPC architecture, is the basis for all new computers made by Apple. Freèscale's MPC74xx processors can be found in Apple's G4 computers. PowerPC processors from Freescale are also ideal for Linux operating system implementations, which are growing in popularity among. desktop users.

IBM Processors

In addition to working with Apple and Freescale PowerPC line, IBM makes high-performance mainframe and workstation CPUs. In 2003, IBM partnered with Apple and re- the G5 (see Figure 4B.7), advertised as the "fastest processor ever. " While most new chips can make this claim, the GS delivered. The G5 delivered true workstation power at the cost of a standard desktop. As a demonstration, Pixar studios were provided with several GS-equipped computers. The Disney/Pixar movie Finding Nemo was created entirely on the G5 desktop computers. Previous releases from Pixar, including ToyStory, required high-end workstations.