Definition and Description

How a Computer Processer Works
Over the last decade, computers have been a huge part of society with almost everybody
having a computer of some sort. Different types of computers have come out such as desktops,
laptops, and tablets. However, Even though the design of machines have changed over the years,
most of the components have remained the same. Many people do not understand what is going
on underneath the stylish design of their computers with these components that are as old as
computers themselves.
This document will be focusing on one component of computers, the central processing
unit (CPU). The CPU is considered the brain of the computer. The CPU’s main task is to receive,
interpret, and give instructions to the rest of the computer. It also performs most of the
calculations that occur in the computer. CPUs are generally small squares with pins on the
bottom that connect to the motherboard.
This document is intended to be for people with prior experience with computers but
without a high level of expertise. Users should understand how to use a computer or some of the
content may be confusing. The information may be simple to users who already have a strong
understanding of CPUs.
Examples of computers today (outside and inside)
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The components of a CPU are the arithmetic logic unit (ALU) and the control unit (CU).
The AU performs the mathematical and logical operations and the CU directs all of the
operations. These components, along with the memory stored in the processor are constantly
working together to successfully run a computer.
Arithmetic Logic Unit
The arithmetic logic unit works with addition, subtraction, multiplication,
and division. It also deals with logical problems such as comparisons between
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characters. The ALU receives a code telling it what operation to perform and it
performs the task. After, it stores the output and shows whether the operation was
Control Unit
The control unit receives information from the computer and sends the
information to the processor. The processor tells the components of the computer
what task to perform based on what it is told by the control unit. This process is
done in the form of electrical signals. The CU directs the rest of the computer
instead of actually performing any tasks.
CPU cycle process – The instructions travel from the main memory to the CU to the ALU
and then goes back into the memory to say whether the process succeeded or failed.
Memory (Cache)
Processors have cache in them as well. Cache is temporary memory inside
of the processor. The memory is not stored long term; because of this, cache is
useful for repetitive tasks but not as useful for tasks without repetition. More
cache, or memory, allows the processor to store more information which makes
some processes occur faster. Cache also assists with background programs
running because the program will be ready for you when you switch to it.
Most computer processors today have more than one core. A core is
another name for the processing unit on the chip; this means that if a CPU has two
cores, it has two processing units. As a general rule, more cores in a processor
means faster performance. The benefit to having extra cores in a computer is that
they do not require another chip meaning they can share one chip slot, power,
cooling, and they can work with the rest of the machine easier.
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The socket is how the processor attaches to the motherboard. The
motherboard is the circuit board that every component in the computer attaches
to; it is generally considered the skeleton of the computer. The CPU must connect
to the motherboard in order for the computer to run. The two most common
brands of processing, Intel and AMD, have different sockets from each other. In
addition to this, different models even within the same brand can have different
sockets. The socket can also affect how a cooler is attached to the motherboard or
if a certain cooler is compatible at all. The socket does not affect the overall
performance of a CPU but must be taken into consideration when choosing a
processor and motherboard combination.
Different CPU sockets: select a CPU that is compatible with the socket on your motherboard.
Source Socket One:
Source Socket Two:
Clock Speed
The clock speed is the number of cycles per second of the processor. All
of the information going through the CPU is executed through cycles; higher
clock speeds means faster cycles and faster processing. The unit for clock speed is
megahertz (MHz), which is 1,000,000 cycles per second, or gigahertz (GHz),
1,000,000,000 cycles per second. Clock speeds can be increased by overclocking
the computer. Overclocking is when the computer pushes the components in the
machine harder to do more work. This creates more heat though and generally the
machine cannot handle the extra heat for an extended period of time without
additional cooling.
Instructions per Cycle
Each processor also has a maximum number of instructions per cycle
(IPC). A higher IPC allows the processor to complete more operations per each
cycle completed by the processor. This means each cycle completed by the
processor accomplishes more making the processor more efficient.
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Hyper-threading is also available as an option in higher end Intel
processing chips. Hyper-threading tricks the computer into thinking it has double
the cores that the chip actually has resulting in stronger processing with some
tasks. This is done by changing the scheduling of the tasks given to the CPU to be
more efficient. Hyper-threading has its biggest advantage when a computer is
attempting to do multiple things at once such as using the internet, Skype, playing
games, and listening to music at the same time. Because hyper-threading does not
actually add cores to the processor, it gives very little benefit to certain tasks such
as doing one thing at a time.
Using a processor creates heat over time. More heat is created if the
processor is forced to work at its maximum for long periods of time. Processors
have a fan that is supposed to keep the processor cool but overworking a
processor or using a low quality fan can still cause a lot of heat. If a processor
becomes too hot, throttling can occur in a machine, which is when the
performance of the component is reduced in order for it to cool down. This
protects the part from getting too hot and causing damage to the hardware.
However, if the processor is constantly overheated or put under heavy loads, parts
can still become damaged over time. The most risk of damage from overheating
comes from leaving the CPU overclocked for extended periods of time without a
proper cooling source. This is why overclocking is generally not recommended
unless higher cooling is available for the processor. However, lack of proper
cooling a can create heat issues even if a CPU is not overclocked. This makes the
cooling of a processor important to the safety and the performance of the CPU.
Example of a CPU cooler and a CPU that is burnt from overheating
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32 vs. 64-Bit
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There are two different types of CPUs: 32-bit and 64-bit. A bit is a unit
used to measure information on a computer. Each type differs in performance and
uses different software from the other. 32-bit processors use only data that is 32
bits wide but 64-bit processors can use both 32 bit and 64 bit processors.
However, a 64-bit processor will run slower with 32-bit software. 64-bit
processors are faster than 32-bit processors because it can process more data.
Also, 64-bit processors support more random access memory (RAM), which
stores data elsewhere in the computer. 64-bit processors are now generally
cheaper than 32-bit processors which are becoming outdated making 64-bit
processors more common and a better choice.
Currently, two brands dominate the market of CPUs – Intel and AMD. The strengths of
Intel processors are speed, power efficiency, and more optimization in the computer. However,
Intel’s processors are more expensive than AMD CPUs. The benefit of AMD processors are the
value for the price, which is important when considering a budget, but come at the cost of using
more power and creating more heat.
Example of an Intel and AMD CPU
Source Intel: Source:
Source AMD:
Why This Information Is Relevant and How It Can Benefit You
The CPU is an integral part of any computer. Many people do not know how CPUs work
and are becoming increasingly confused with the expanding options being developed in today’s
market. It is important to understand what a CPU does and how it functions to understand what is
happening inside of your computer. This is beneficial to optimizing the function of your
computer as well as keeping your computer well maintained. Understanding how a CPU works is
a strong way of understanding your needs when choosing a computer or troubleshooting an issue
with a computer.
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Works Cited
“CPU.” Computer Hope. Web. 22 March 2015
“CPU – Central Processing Unit.” Webopedia. Web. 22 March 2015
“How Computers Work: The CPU and Memory.” Web. 22 March 2015
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“How Computers Work: The CPU and Memory,”