|
Just like the human brain processes information and directs the body to perform certain actions, it processes instructions and directs the operations of the computer.
The CPU may also be called the Microprocessor or the Computer Processor
By whatever name it is called, it is the component that actually does the 'thinking'. All the other parts of the computer are designed around it.
The processor isn't just a very important component of the computer; it's crucial! Without one, the system couldn't perform. In other words, a computer system without a CPU, would be like a car without an engine -It simply wouldn't perform at all!
The reliability of your computer system is determined by the quality of your computer processor. The type of motherboard that you use would be determined by your choice of processor.
You can look at some very good prices on a wide range of Cheap Computer CPUs here.
The microprocessor consists of three sections:
- The ALU (Arithmetic Logic Unit).
- Registers.
- Control Unit.
.jpg "The Inside of a CPU")
These three sections of the microprocessor work together to control the operations of the system. They are connected to the system bus and handle the input, output and storage of data.
Let's examine the three sections of the microprocessor in more detail:
ALU (Arithmetic Logic Unit) - This unit performs the computing functions involving integers (whole numbers).
- Arithmetic operations which include addition, subtraction, multiplication and division.
- All logic operations which involve comparisons such as less than, greater than, or equal to.
All information in a CPU is reduced to a numeric function; therefore, the ALU is constantly handling arithmetic and logic operations.
The results of these operations are stored in the registers or in memory or sent to output devices.
Registers - All data is temporarily stored in registers during the execution of programs and the size of the internal register determines how much information the CPU can process at one time.
Control Unit - This unit handles the timing and control signals to all the operations in the system. You can compare the control unit to a police officer directing traffic at a busy intersection; but, instead of directing cars, the control unit directs data flow between the computer processor and peripherals and memory.
This basically wraps up the functions of the three sections of the CPU.
You can check out my guide to installing the
Computer Processor and Heat Sink/Fan Assembly here.
There are some other terms you will need to become familiar with before continuing, such as:
System Bus:
The CPU transfers data to other components in the system through the system bus. The system bus or processor bus is an external data bus. External data bus describes the wires and traces on the motherboard that are used to send and receive data.
The greater the amount of wires, the more data you can send and receive. In the first set of PCs, the bus was 8 bits wide, meaning that 8 bits could be transferred at the same time. (In the binary numbering system, a bit is a single digit, either a '1' or a '0'. A combination of 8 bits is called a byte).
Systems advanced and a faster rate of processing more data, became necessary. As this need for faster processing of data increased, the bus width was expanded to 16 bits, then to 32 bits and then to 64 bits. A 64-bit bus can carry eight times as much data as an 8-bit bus.
With improvements in technology, CPUs capable of handling large amounts of data were manufactured. Therefore, the buses had to be widened to facilitate the movement of huge amounts of data being processed.
Cache:
A cache is a small amount of high speed memory provided to hold data. Some CPUs have cache which vary from 8 KB to 2 MB of static RAM (SRAM). Static ram performs much faster than dynamic RAM (DRAM) which is used for the systems main memory.
The data requested by the CPU, is handled by the cache controller. The cache controller may be built into the processor or it may be built on the motherboard. Overall, cache dramatically increases the speed at which the computer processes data.
Because this cache is internal, it can be accessed directly and keeps up with the speed of the microprocessor. Without this cache, the microprocessor would have to wait for the data to come from the main memory.
Math Co-processor:
The Math co-processsor (also called the FPU or floating-point unit) handles decimal calculations. In computer language, these calculations are called floating-point math. These calculations slow down the processor but if a math coprocessor is present, it performs these operations much faster.
You have now learnt about the basic internal components of a computer processor. Let's go further and take a look at how it functions.
How does a CPU Work?
The processor performs three basic functions such as:
- It accepts input.
- Processes data.
- Provides output.
Here are the three basic functions:
Input:
This is the process by which external data is received into the computer. This could either be running a program or getting keyboard responses. Common inputs include a keyboard, mouse, modem, scanner, etc.
The computer system analyzes the input data.
Process:
Process describes the converting of input into output and is generally guided by a program.
Output:
Output is the process by which the CPU sends data to devices such as the monitor, printer, disk drive, etc. Output takes the results of the processing and sends them to be stored in memory or printed or displayed.
Output is the final result of the processing of the data that was input and used by the computer system.
Data must be stored either temporarily or permanently. Therefore, this is where memory is required. The computer needs a way to hold onto data as the processing is being performed.
Memory
The computer stores data in memory and retrieves the data it needs from memory. There are two kinds of memory - ROM and RAM.
ROM (Read-Only Memory) is permanent and will be retained even when the computer is turned off.
RAM (Random Access Memory) is volatile and data stored in RAM will be erased when the computer is turned off. The processor uses RAM to store data and retrieves data from RAM as it's needed. The instructions of a program, for example, would be stored in RAM. RAM will be lost if the computer loses power.
CPU Limitations
Having described the computer processor and how it works, we now need to know its capabilities and limitations.
CPU Cooling
Very little power was consumed by the earlier processors but the newer processors consume much more power. Processors will crash or malfunction if overheated; therefore, it is of utmost importance that they have adequate cooling.
Of the two main brands of CPUs (AMD and Intel), AMD is more susceptible to overheating damage than Intel. This is caused by the smaller core size of the AMD as compared to the larger core size of the Intel processor. The larger core size dissipates heat faster.
Although there are different methods of CPU cooling, the most popular method is the heat sink/fan assembly.
The heat sink/fan assembly must be securely mounted to the processor after applying thermal compound to the core. Thermal compound assists in the fast dissipation of heat.
EXERCISE EXTREME CAUTION when using the screwdriver to install the heat sink clip since the screwdriver could slip and damage the motherboard.
Substandard cooling can cause maximum operating temperatures to be exceeded. This may or may not damage the CPU but could cause crashes in processors such as the AMD. This malfunction generally disappears when the processor cools down.
In the case of the Pentium 4, if it overheats, it will automatically reduce its speed thus avoiding damage. Sometimes this reduction in speed goes unnoticed.
If you operate the processor without a heat sink, AMD CPUs will generally be permanently damaged unless the motherboard is equipped with special protection circuitry.
Browse for some
heat sink fan assemblies here.
Intel and AMD CPUs
Processors are constantly being developed and this can be seen in the advancement of newer and faster CPUs.
Intel and AMD are the two main brands of CPUs with Intel being the first to release a processor to the computer world. The market is now being shared by both Intel and AMD with a small part for the Via/Cyrix processors.
- Intel and AMD release dual-core computer chip
Intel and AMD have both launched a dual-core computer chip which combines two microchips into one. This means one chip will have two cores that will be able to perform tasks independently of each other.
The present Intel CPUs include the Pentium III, Celeron, Pentium 4 and Pentium 4 with Hyper Threading. Improving on these platforms are the new Core Duo, Core 2 Duo and Core 2 Extreme. The Core 2 Duo is the new Quad Core platform. This processor family is designed with about 40% increase in speed for powerful, energy-efficient performance which enables them to do more at once without slowing down.
The Intel Centrino Duo Mobile technology has been upgraded with the new Intel Core 2 Duo Mobile CPU. It doubles multi-tasking with improved energy efficiency. This factor provides for longer battery life and makes it possible to have a powerful dual-core computer with mobility.
The Intel Core 2 Extreme dual-core processor (Intel Core 2 Extreme X6800) is now the best gaming CPU. It provides energy-efficient gaming performance and great high-definition multimedia. This is due to its whopping 4MB of L2 cache and up to 1066 MHz of front side bus (FSB). This "baby" is built for speed!
The Intel Core 2 Extreme quad-core processor (Intel Core 2 Extreme QX6800) is designed with 4 processing cores. It makes multi-tasking easy by doubling the performance on highly-threaded applications. It is also a superb gaming performer and is ready to take on any and everything even the highly-threaded games of the future.
These Intel CPUs all use the LGA775 socket.
The present AMD CPUs include the Duron, Athlon, Athlon XP, Sempron, Opteron, Turion 64, Turion 64 X2, Athlon 64, Athlon 64 X2, Athlon 64 FX and Quad FX.
The AMD Sempron is available in two applications - Desktop and Mobile. This processor is used in full-featured desktops and notebooks for performing regular everyday computing.
The AMD Turion 64 mobile technology is designed to deliver AMD64 performance. It is suitable for thin and light laptops and provides longer battery life and enhanced security. It is compatible with the present wireless and graphics technologies.
The AMD Turion 64 X2 dual-core mobile processor is the most advanced mobile dual-core processor. It delivers superb multi-tasking for today's thin and light notebooks.
The AMD Athlon 64 X2 dual-core processor increases performance by up to 80%. You can run multiple programs simultaneously without noticing any drop in performance. This dual-core technology performs like two processors working together. Two processors working together is more efficient than one working alone.
The AMD Athlon 64 FX processor uses AMD's most advanced processor technology. This processor comes in single and dual-core and are for PC enthusiasts who "live" in the digital world. It executes high gaming levels and controls digital media with great ease while enabling mega-tasking. It's "out of this world" for the future of the digital media and gaming experiences.
The AMD Quad FX technology features a Dual Socket Direct Connect Architecture that uses 4 processing cores with the ability to seamlessly upgrade to 8 cores. The Direct Connect Architecture is an AMD exclusive high-bandwidth interconnect design for coupling two multi-core CPUs.
The AMD Quad FX also has an onboard memory controller that reduces memory access latency and enhances performance while mega-tasking.
Despite AMD's fall from dominance in the processor race, it has introduced its Quad-Core CPU - Quad-FX and has intentions of releasing an Eight-Core processor by late 2007.
These AMD processors use a variety of sockets namely:
Socket 754, 939, 940 and the new AM2.
Following are the three categories of CPUs:
- Low-End - This group includes the AMD Sempron and the Intel Pentium 4 which are usually found in many homes and small businesses. They are inexpensive and ideal for performing tasks such as word processing, spreadsheets, surfing the web and medium graphics.
The AMD Sempron uses Socket 754 and the Intel Pentium 4 uses the Socket 478.
- Mid-Range - Included in this group are the AMD Athlon 64 and the Intel Pentium D processor 945. These costs a little more but can perform more demanding tasks such as data bases, heavy graphics and playing advanced games.
The Athlon 64 CPU uses the Socket 939 and the Pentium D processor uses the Socket 775.
- High-End - This group includes the AMD Opteron, Athlon 64, Athlon 64 X2, Athlon 64 FX, Intel Core Duo, Intel Core 2 Duo and the Intel Core 2 Extreme. These are multimedia systems and can perform heavy graphics-intensive tasks and multi-tasking. These processors cost a 'pretty penny'.
The AMD Athlon 64 uses the Socket 754, the Athlon 64 FX, the Opteron uses the Socket 940 and the Athlon 64 X2 uses the new socket AM2. The Intel Core Duo, Core 2 Duo and the Core 2 Extreme use the Socket 775.
For anyone considering the building of their own cheap computer using cheap computer parts, the AMD Athlon 64 X2 provides a better price-performance ratio.
But, if you need speed and you got cash, check out the "wicked" Intel Core 2 Extreme X6800!
Click here and view some fantastic prices on AMD and Intel Processors.
Buying a boxed versus Open Box CPU
It is better to buy a boxed processor for the following reasons:
- They usually come with the heat sink and fan assembly.
- The manufacturer's warranty is also included.
The open box processors do not come with a heat sink/fan assembly and they do not have a manufacturer's warranty; instead, they come with the Dealer's Warranty.
Conclusion
I have given you a concise guide to cheap computer CPUs. The choice is now yours.
One final advice......Don't be fooled by sales 'pitches' recommending an 'upgradeable' CPU. This is an added cost which at most times is impractical since, by the time an upgrade is necessary, other components will also need to be upgraded.
Replacing the system would be more economical but, if you are electronically inclined and like to 'play around' with building cheap computers, you could upgrade the CPU. Otherwise, my recommendation to you is do not upgrade!
Browse here for all the steps in the
Build Your Own Cheap Computer tutorial
Click here now and look at my BEST Online Cheap Computer Retailers' Guide. This guide allows you to visit a number of the BEST online Cheap Computer Retailers. Click here to view.
Return from Cheap Computer CPU to
Cheap Computer Home Page
