Hardware Reference
In-Depth Information
Chapter 3. Processor Types and Specifications
Microprocessor History
The brain or engine of the PC is the processor—sometimes called
microprocessor
or
central
processing unit
(CPU). The CPU performs the system's calculating and processing. The processor is
one of the two most expensive components in the system (the other being the video card). In higher-
end systems, the processor can cost up to four or more times more than the motherboard it plugs into.
Intel is generally credited with creating the first microprocessor in 1971 with the introduction of a
chip called the 4004. Today Intel still has control over the processor market, at least for PC systems,
although AMD has garnered a respectable market share. For the most part, PC-compatible systems
use either Intel processors or Intel-compatible processors from AMD.
Tip
One of the easiest ways to learn about your computer's processor (speed, number of cores, and
cache sizes), chipset, and other features is to run the free CPU-Z program. You can download it
from
www.cpuid.com
.
Later in this chapter, you will see how CPU-Z works to display system
information.
It is interesting to note that the microprocessor had existed for only 10 years prior to the creation of
the PC! Intel released the first microprocessor in 1971; IBM created the PC in 1981. Over three
decades later, we are still using systems based more or less on the design of that first PC. The
processors powering our PCs today are still backward compatible in many ways with the Intel 8088
that IBM selected for the first PC in 1981.
The First Microprocessor
Intel was founded on July 18, 1968 (as N M Electronics) by two ex-Fairchild engineers, Robert
Noyce and Gordon Moore. Almost immediately, they changed the company name to Intel and were
joined by cofounder Andrew Grove. They had a specific goal: to make semiconductor memory
practical and affordable. This was not a given at the time, considering that silicon chip-based
memory was at least 100 times more expensive than the magnetic core memory commonly used in
those days. At the time, semiconductor memory was going for about a dollar a bit, whereas core
memory was about a penny a bit. Noyce said, “All we had to do was reduce the cost by a factor of a
hundred, then we'd have the market; and that's basically what we did.”
By 1970, Intel was known as a successful memory chip company, having introduced a 1Kb memory
chip, much larger than anything else available at the time. (1Kb equals 1,024 bits, and a byte equals 8
bits. This chip, therefore, stored only 128 bytes—not much by today's standards.) Known as the 1103
dynamic random access memory (DRAM), it became the world's largest-selling semiconductor
device by the end of the following year. By this time, Intel had also grown from the core founders and
a handful of others to more than 100 employees.
Because of Intel's success in memory chip manufacturing and design, Japanese manufacturer Busicom
asked Intel to design a set of chips for a family of high-performance programmable calculators. At the
time, all logic chips were custom-designed for each application or product. Because most chips had
