CHAPTER 2 MICROPROCESSORS

Introduction :
	Computer is capable of performing complex tasks, such as managing the brake system of a car. These tasks are processed by the Central Processing Unit (CPU). The CPU comprises of the microprocessor. The microprocessor accepts input from the user in the form of the data and instructions. It processes the data using the instructions and sends the processed information to the output device. The microprocessor controls the system, therefore it is important to understand it's working. The choice of the microprocessor also depends on computing needs.
2.1 Overview of Microprocessors
	The microprocessor is a chip that accepts data and instruction, processes it and gives the output. An instruction is a calculation that the microprocessor processes such as adding two numbers. One of the key elements of the microprocessor is its speed. The speed of the microprocessor depends on various factors such as the number of instructions it processes, the bandwidth, and the clock speed. The bandwidth specifies the number of binary digits that the microprocessor can process in a single instruction. The clock speed specifies the speed at which the microprocessor processes an instruction.The speed of the microprocessor also depends on the number of the transistors built into the processor. The transistors in the microprocessor boost the data signals on the processor. The more the transistors built on the microprocessor the faster is the speed of the microprocessor. The advancements in technology have reduced the size of the transistors and have increased the processing speed of the processor. Microprocessors may also have a cache to store information. The microprocessor can access information faster from the cache than from the RAM.
2.2 Evolution of Microprocessors
	Intel created the first microprocessor in the year 1971. Over the years, Intel has modified the microprocessor to make it faster, efficient, and reliable. Intel released the 4004 microprocessor in the year 1971, which was used in Busicom calculators. The 8008 microprocessor was created in the year 1972. These microprocessors were used in bottling machines and systems that needed little processing. Intel released the 4040 and 8080 microprocessor in the year 1974. The 4040 was the 4004 microprocessor with extra instructions built into it such as logical and comparative capabilities. The 8080 microprocessor was the first microprocessor for the personal computer and was used in the computer called Altair. In 1979, the 8088 microprocessor was created for use in the personal computers manufactured by International Business Machines (IBM). In the year 1982, Intel created the 80286 microprocessor for desktop computers. This microprocessor was superior to the 8088 microprocessor in speed because the number of transistors on the microprocessor was increased. Intel also released the 80386 series and the 80486 series of microprocessors that processed data faster than the previous microprocessors. Intel went on to categorize microprocessors into families based on the need and use of the systems. The speed, performance, and price of a microprocessor differ from one microprocessor family to another. The launch of Intel Pentium microprocessor in 1993 enabled system to execute programs that required a lot of processing. Intel then gradually went on to develop the Pentium II, Celeron, Xeon, Pentium III, and Pentium 4 for different purposes.
	2.2.1 Intel Pentium
	The Intel Pentium microprocessors are designed to work with everyday applications, such as word processors, spreadsheets, multimedia applications, and games. The Intel Pentium family of processors is built with the power to work with all these applications. 1971 4004 1972 8008 1974 4040 / 8080 1979 8008 1982 80286 1985 80386 series 1989 80486 series 1993 Pentium family 1997 Pentium II Family 1998 Celeron / Xeon family 1999 Pentium III family 2000 Pentium 4 family
	Intel Pentium I Processor
	The Intel Pentium I processor was released in the year 1993. The Intel Pentium I microprocessor is the first chip in a line up that forms the fifth generation of microprocessors. The fifth generation of microprocessors uses different motherboard architecture as compared to the motherboards used by the previous generation processors. The speed of the fifth generation microprocessor is double the speed of the previous microprocessor.The main feature that differentiates the Pentium I from the previous processors is that the Pentium I processor has two pipelines. This feature enables the Pentium microprocessor to execute multiple instructions simultaneously. The Pentium I has a 5-stage pipeline for executing instructions.
	Processor Clock Speed Mfg. Process Number of (MHz) (micron) Transistors (million)
	Intel Pentium Processor with MMX Technology 233 0.35 4.5 Intel Pentium Processor with MMX Technology 200, 166 0.35 4.5 Intel Pentium Processor 200, 166 0.35 3.3 Intel Pentium Processor 166, 150 0.35 3.3 Intel Pentium Processor 133 0.35 3.3 Intel Pentium Processor 120 0.6, 0.35 3.2 Intel Pentium Processor 100, 90 0.6 3.2 Intel Pentium Processor 75 0.6 3.2 Intel Pentium Processor 66, 60 0.8 3.1
	Intel Pentium II Processor
	The Intel Pentium II processor was released in the year 1997. The reduction in the size of transistors and wires on the chip enables the installation of additional transistors on the chip. This has increased the speed at which the chip processes the instructions. Hence, the processor provides increased performance as compared to the Pentium I processor. The Pentium II processor provides support to work with applications developed for Pentium I. The Intel Pentium II processor is available on a card known as the daughter card. The daughter card must be affixed on the motherboard using Slot 2. The daughter card has the L2 cache built into it.The microprocessor communicates with the L2 cache at the full processor speed of 150 MHz whereas it communicates with the external memory such as the RAM at the speed of 66 MHz. The Pentium II has a 14-stage pipeline for executing instructions. The increase in the stages allocates the instruction execution over the different stages. This executes the instruction faster.
	Processor Clock Manufacturing Number of Cache Bus Speed Speed Process Transistors (MHz) (MHz) (micron) (million)
	Intel Pentium II 450 0.25 7.5 512 KB on-die 100 Processor L2 cache Intel Pentium II 400, 350 0.25 7.5 512 KB on-die 100 Processor L2 cache Intel Pentium II 333 0.25 7.5 512 KB on-die 66 Processor L2 cache Intel Pentium II 300, 266, 233 0.35 7.5 512 KB on-die Processor L2 cache
	Processor Clock Manufacturing Number of Cache Bus Speed Speed Process Transistors (MHz) (MHz) (micron) (million)
	Intel Pentium II 450 0.25 7.5 512 KB on-die 100 Processor L2 cache Intel Pentium II 400, 350 0.25 7.5 512 KB on-die 100 Processor L2 cache Intel Pentium II 333 0.25 7.5 512 KB on-die 66 Processor L2 cache Intel Pentium II 300, 266, 233 0.35 7.5 512 KB on-die Processor L2 cache On-die specifies that the cache is built into the daughter card.
	Intel Pentium III Processor
	The Intel Pentium III microprocessor was released in the year 1999. The Pentium III microprocessor is built with a unique Processor Serial Number (PSN) embedded in the chip. The PSN number when activated works as a system security tool. For example, while purchasing goods over the Internet both the buyers and the sellers system can be identified using the system PSN number. The Pentium III has more instructions than the Pentium II built into the microprocessor to process graphics. The Pentium III has a 10-stage pipeline for executing instructions.
	Processor Clock Manufacturing Number of Cache Bus Speed Speed Process Transistors (MHz) (micron) (million)
	Intel Pentium III 1 GHz, 933 MHz, 0.18 28 256 KB 100, 133 Processor 866 MHz, Advanced 850 MHz Transfer cache Intel Pentium III 733 MHz, 700 MHz, 0.18 28 256 KB 100, 133 Processor 667 MHz, 650 MHz, Advanced 600 MHz, 550 MHz, Transfer 533 MHz, 500 MHz cache Intel Pentium III 600 MHz, 550 MHz, 0.25 9.5 512 KB 100 Processor 500 MHz, 450 MHz
	Intel Pentium 4 Processor
	The Intel Pentium 4 processor was released in the year 2000. This processor enables us to work with applications such as digital photography that require a lot of processing. The Pentium 4 has a 20-stage pipeline for executing instructions. The Pentium 4 microprocessor comes in two sizes. The first microprocessors were large in size with 423 pins. These processors only supported RDRAM. Intel later decreased the size of the Pentium 4 microprocessor and increased the number of pins to 478. The microprocessor now supported SDRAM. The RDRAM and SDRAM are different types of memory. The Pentium 4 microprocessor is also available in the Hyper-Threading (HT) edition and the HT Extreme edition. The HT technology enables the microprocessor to process two parts of the program simultaneously. This ensures that the program executes faster. The Pentium 4 HT edition is targeted for gamers because 3D games such as Counter Attack and FIFA Football 2004 are complexprograms and require a lot of processing.The Pentium 4 HT Extreme edition is similar to the Pentium 4 HT edition. The only difference is that this edition has an additional 2 MB of L3 cache built into the microprocessor.
	Processor Clock Manufacturing Number of Cache Bus Speed Speed Process Transistors (MHz) (GHz) (million)
	Intel Pentium 4 3.40, 3.20 0.13-micron 178 2 MB L3 cache, 800 Processor 512 KB L2 Extreme Edition cache (HT Technology) Intel Pentium 4 3.60, 3.4, 90 nano- 125 1 MB L2 800 processor 3.2, 3, 2.80 micron cache supporting HT Technology 560,550, 540, 530,520 Intel Pentium 4 3.40, 3.20, 90 nano- 125 1 MB L2 800Processor 3, 2.80 micron cache (HT Technology) Intel Pentium 4 3.40, 3.20, 0.13-micron 55 512 KB 800 Processor 2.80, 2.60, Advanced (HT Technology) 2.40 Transfer L2 cache Intel Pentium 4 3 0.13-micron 55 512 KB 800 Processor Advanced (HT Technology) Transfer L2 cache Intel Pentium 4 3.06 0.13-micron 55 512 KB 533 Processor Advanced (HT Technology) Transfer L2 cache Intel Pentium 4 2.80, 2.66, 0.13-micron 55 512 KB 533 Processor 2.53, 2.40, Advanced 2.26 Transfer L2 cache Intel Pentium 4 2.60, 2.50, 0.13-micron 55 512 KB 400 Processor 2.40, 2.20, Advanced 2 Transfer L2 cache Intel Pentium 4 2, 1.90, 1.80, 0.18-micron 42 256 KB 400 Processor 1.70, 1.60, Advanced 1.50, 1.40 Transfer L2 cache
	2.2.2 Intel Pentium M
	Laptops and notebook computers use the Intel Pentium M microprocessors. These microprocessors consume less energy and prolong the battery life of the notebook computer. These microprocessors are smaller in size compared to the microprocessors used in the desktop computers.
	Processor Clock Manufacturing Number of Cache Bus Speed Speed Process Transistors (MHz) (GHz) (million)
	Intel Pentium M 2, 1.80, 90 nano- 77 2 MB 400 Processor 1.70, 1.60, micron 755, 745, 735, 1.50 725, 715 Intel Pentium M 1.70, 1.60, 0.13-micron 77 1 MB Low 400 Processor 1.50, 1.40, Power L2 1.30 cache
	2.2.3 Intel Celeron
	The Celeron is useful for running applications that do not require a lot of processing. The Celeron microprocessor architecture is based on the Pentium microprocessor architecture. The Celeron microprocessors are cheaper and economical because of the small cache size.
	Processor Clock Manufacturing Cache Bus Speed Speed Process (MHz)
	Intel Celeron D Processor 2.80 GHz, 90 nano- 256 KB L2 533 335, 330, 325, 320 2.66 GHz, micron cache 2.53 GHz, 2.40 GHz Intel Celeron Processor 2.80 GHz, 0.13-micron 128 KB 400 2.70 GHz Advanced Transfer L2 cache Intel Celeron Processor 2.40 GHz, 0.13-micron 128 KB 400 2.30 GHz, Advanced 2.20 GHz, Transfer 2.10 GHz L2 cache Intel Celeron Processor 2 GHz 0.13-micron 128 KB 400 Advanced Transfer L2 cache Intel Celeron Processor 1.80 GHz, 0.18-micron 128 KB 400 1.70 GHz Advanced Transfer L2 cache Intel Celeron Processor 1.40 GHz, 0.13-micron 256 KB 100 1.30 GHz, Advanced 1.20 GHz Transfer L2 cache Intel Celeron Processor 1.10 GHz, 0.18-micron 128 KB 100 1 GHz, Advanced 950 MHz, Transfer 990 MHz, L2 cache 850 MHz, 800 MHz Intel Celeron Processor 766 MHz, 0.18-micron 128 KB 66 733 MHz, Advanced 700 MHz, Transfer 667 MHz, L2 cache 633 MHz, 600 MHz, 566 MHz Intel Celeron Processor 533 MHz, 0.25-micron 128 KB 66 500 MHz, Advanced 466 MHz, Transfer 433 MHz, L2 cache 400 MHz, 366 MHz, 333 MHz, 300 MHz Intel Celeron Processor 300 MHz, 0.25-micron NA 66 266 MHz
	2.2.4 Intel Xeon
	Intel Xeon microprocessors are heavy-duty microprocessors. These microprocessors powers servers and workstations on a network. The Xeon microprocessor supports two microprocessors on the same system.
	Processor Clock Manufacturing Number of Cache Bus Speed Process Transistors Speed (GHz) (Micron) (million) (MHz)
	Intel Xeon Processor 3 0.13 169 4 MB Integrated MP L3 Cache 400 Intel Xeon Processor 2.80, 2.70, 0.13 169 2 MB Integrated 400 MP 2.20 L3 Cache Intel Xeon Processor 2, 1.90, 1.50 0.13 108 2 MB, 1 MB 400 MP Integrated L3 Cache Intel Xeon Processor 1.60, 1.50, 0.18 108 256 KB Adv. 400 MP 1.40 Transfer L2 Cache, 8 KB Execution Trace L1 Cache Intel Xeon Processor 3.20 0.13 108 1 MB L3 Cache 533 Intel Xeon Processor 3.06 0.13 108 1 MB L3 Cache 533 Intel Xeon Processor 3.06 0.13 108 512 KB L2 533 Cache Intel Xeon Processor 2.80, 2.60, 0.13 108 512 KB L2 533 2.40, 2 Cache
	2.2.5 Intel Itanium
	Intel Itanium microprocessor powers network servers and workstations. For example, dedicated servers that handle database requests and email servers use the Intel Itanium processors. It is a powerful microprocessor and can execute three instructions at a time. It is a Reduced Instruction Set Computing (RISC) microprocessor and has limited instructions built into the microprocessor.
	Processor Clock Manufacturing Number of Cache Speed Process Transistors (Micron) (million)
	Intel Itanium 2 Processor 1.60 GHz - 0.13 410 3 MB L3 Cache 1.40 GHz Intel Itanium 2 Processor 1.40 GHz 0.13 410 1.5 MB L3 Cache (for dual processor systems) Intel Itanium 2 Processor 1.50 GHz 0.13 410 6 MB L3 Cache Intel Itanium 2 Processor 1 GHz, 0.18 220 3 MB and 900 MHz 1.5 MB L3 Cache Intel Itanium Processor 800 MHz - 0.18 25 2 MB and 733 MHz 4 MB L3 Cache
	2.2.6 AMD
	The AMD Duron and Athlon microprocessors were developed by Advanced Micro Devices (AMD). Athlon is the heavy-duty microprocessor available from AMD and is similar to Pentium microprocessors. Duron microprocessors are similar to the Pentium Celeron microprocessors. Intel Pentium II uses Slot 1 to connect to the motherboard. Intel patented this slot and the competitors could not create a microprocessor to use this slot. AMD with the help of VIA Technologies, Inc, created the motherboard that uses Slot A to connect the AMD microprocessor to the motherboard.
2.3 Microprocessor Designs
	The microprocessor is installed on the motherboard. The microprocessor is designed to fit into a motherboard based on the type of the socket or the slot used to connect it.
	2.3.1 Microprocessor Sockets
	The socket on the motherboard connects the microprocessor to the motherboard. The microprocessor has pins that enter the motherboard using which the microprocessor communicates with the system. Motherboards that use the socket to install the microprocessor use the Zero Insertion Force (ZIF) or the Low Insertion Force (LIF) design to install the microprocessor on the motherboard. The ZIF uses a lever to install or remove the microprocessor, thus the microprocessor can be installed and removed without using any force. You must use force to push the microprocessor in the LIF socket. You must use special tools such as a screwdriver or a chip puller to remove the microprocessor from the LIF socket.
	Microprocessors support different voltages. The voltage required by the microprocessor is adjusted automatically by the microprocessor, however you may have to adjust the jumpers on the older motherboard. Jumper is a switch present on the hardware that enables you to configure the hardware.
	Socket 1
	Socket 1 supports microprocessors that have 169 pins. In this socket, the pins are arranged in three rows. Socket 1 supplies maximum 5 volts to the microprocessor. This socket supports the 80486 and 80486 OverDrive microprocessor. The Overdrive microprocessor can be installed on different sockets. These are used on older motherboards.
	Socket 2
	Socket 2 supports microprocessors that have 238 pins. In this socket, the pins are arranged in four rows. Socket 2 supplies maximum 5 volts to the microprocessor. This socket supports the 80486 and Pentium OverDrive microprocessors.
	Socket 3
	Socket 3 supports microprocessors that have 237 pins. In this socket, the pins are arranged in four rows. Socket 3 supplies 3.3 to 5 volts to the microprocessor. The voltage can be adjusted using the jumpers on the motherboard. This socket supports the 80486, AMD 5x86, and Pentium OverDrive microprocessors.
	Socket 4
	Socket 4 supports microprocessors that have 273 pins. In this socket, the pins are arranged in four rows. Socket 4 supplies maximum 5 volts to the microprocessor. This socket supports the Pentium 60-66, and Pentium Overdrive microprocessors.
	Socket 5
	Socket 5 supports microprocessors that have 320 pins. In this socket, the pins are arranged in five rows. Socket 5 supplies maximum 3.3 volts to the microprocessor. This socket supports the Pentium 75-133 MHz, Pentium OverDrive microprocessors.
	Socket 6
	Socket 6 supports microprocessors that have 235 pins. In this socket, the pins are arranged in four rows. Socket 6 supplies maximum 3.3 volts to the microprocessor. This socket supports the 80486 microprocessor.
	Socket 7
	Socket 7 supports microprocessors that have 321 pins. In this socket, the pins are arranged in five rows. Socket 7 supplies 2.5 to 3.3 volts to the microprocessor. The processors for this socket use 2.5 volts for input-output, whereas the core of the microprocessor uses 3.3 volts. This socket supports the Pentium 75-200 MHz, and Pentium OverDrive microprocessors.
	Socket 8
	Socket 8 supports microprocessors that have 387 pins. In this socket, the pins are arranged in five rows. Socket 8 supplies 3.1 to 3.3 volts to the microprocessor. This socket supports the Pentium Pro microprocessors. The Socket 8 is more rectangular in shape than the other sockets.
	Socket 370
	Socket 370 supports microprocessors that have 370 pins. In this socket, the pins are arranged in six rows. The microprocessors for this socket have the L2 cache built into the microprocessor. This socket supports Celeron 2 and Pentium III microprocessors.
	Socket 462
	Socket 462 is also known as Socket A. This socket supports microprocessors that have 462 pins. The microprocessors for this socket have the L2 cache built into the microprocessor. This socket supports the Athlon and Duron microprocessors.
	Socket 478
	Socket 478 supports microprocessors that have 478 pins. The microprocessors for this socket have the L2 cache built into the microprocessor. The Socket 478 microprocessor supports the Intel Pentium 4 microprocessor.
	2.3.2 Microprocessor Slots
	Microprocessors such as the Intel Pentium II, III, Xeon, Celeron, and AMD Athlon are installed on cards. The card with the microprocessor on it is installed on the motherboard. The card is built in with the L2 cache. This speeds up the processing because the processor can store the instructions in this cache.
	Slot 1
	Slot 1 supports microprocessors that have 242 pins. The microprocessor is mounted on a card that uses Socket 8. Slot 1 supplies 2.8 to 3.3 volts to the microprocessor. This slot supports the Pentium II, III, and Celeron microprocessors.
	Slot 2
	Slot 2 supports microprocessors that have 330 pins. This slot supports the Pentium Xeon microprocessors. This slot is found on server motherboards.
	Slot A
	Intel patented the Slot 1. This allowed only Intel to manufacture microprocessors that used this slot. AMD created the Slot A to support the Athlon microprocessors. This Slot A uses the EV6 protocol that enables the microprocessor and the RAM to communicate at an increased speed.
2.4 Working of the Microprocessor
	The microprocessor is a complex chip in the system. The different parts of the microprocessor work together to process the data and give the user information. The various parts of a microprocessor are as follows.
	Input – Specifies the system input devices
	Output – Specifies the system output devices
	Arithmetic and Logic Unit (ALU) –Performs all the arithmetic calculations such as addition and subtraction and the logical calculations such as the AND and OR operators
	Control Unit (CU) – Controls the flow of the data and information to other units of the microprocessor
	Memory / Cache – Stores the data and instruction required by the microprocessor The data and the instructions for processing the data enter the microprocessor from the input device such as the keyboard. The CU stores the data and the instructions in the Memory / Cache and sends the instructions to process the data to the ALU. The CU retrieves the data required by the instructions in the ALU from the Memory / Cache. The ALU processes the data using the instructions and sends the result to the CU. The CU stores the result in the Memory / Cache and sends it to the output device such as the monitor or printer when required.
2.5 Interface of the Microprocessor
	Data and information flows from the microprocessor to the different devices connected to the system. Hardware devices such as the hard disk, floppy disk, and printer are connected to the microprocessor using a bus. The size of the bus determines the amount of information that can travel between the two devices in a clock speed of the microprocessor. There are two types of buses, the serial bus and the parallel bus. On a serial bus, the data travels between two devices one bit at a time. On a parallel bus, more than one bit of information can travel between two devices. The steps the microprocessor follows to interface with a device are :
	1. The microprocessor checks the status of the device.
	2. The microprocessor requests the device for transferring data.
	3. The device sends the data request to the microprocessor.
	4. The microprocessor sends the required data to the device.
2.6 Installing the Microprocessor
	The microprocessor and the motherboard are dependent on each other. Before, we install the microprocessor, we must check that the motherboard and the microprocessor voltage are compatible with each other.
	Hands on exercise
	The Zero Insertion Force (ZIF) socket uses a lever that makes it simpler and safer to install the microprocessor on the motherboard. This socket also makes it easy to remove the microprocessor 40 from the motherboard without damaging the pins located on the underside of the microprocessor or the microprocessor itself.
	To install the processor in the ZIF socket :
	1. Check the voltage requirements from the motherboard and the microprocessor documentation.
	2. Wear an anti-static wristband.
	3. Place the motherboard on the work desk.
	4. Take the microprocessor out from the anti-static bag by holding the microprocessor at the edges.
	5. Check that all the pins on the underside of the microprocessor are straight.
	6. Locate the socket where the microprocessor must be installed
	Location to Install the Microprocessor
	7. Find the lever located besides the socket for the microprocessor.
	Viewing the Lever
	8. Raise the lever so that it is at the right angle with the motherboard.
	9. Align the notch on the microprocessor with the alignment notch on the motherboard.
	Aligning the Microprocessor
	10. Gently, place the microprocessor in the socket.
	11. Press the microprocessor firmly in the socket keeping in mind that no damage is caused to the pins.
	12. Push the lever back down such that it is parallel to the motherboard and locked in place, taking care not to break the lever while lowering it .
	Locking the Lever to Install the Microprocessor
	Hands on exercise
	The Low Insertion Force (LIF) socket does not have a lever to install the microprocessor. We must force the microprocessor into the motherboard socket to install it.
	To install the processor in the LIF socket:
	1. Check the voltage requirements from the motherboard and the microprocessor documentation.
	2. Wear an anti-static wristband.
	3. Place the motherboard on the work desk.
	4. Take the microprocessor out from the anti-static bag by holding the microprocessor at the edges.
	5. Check that all the pins on the underside of the microprocessor are straight.
	6. Locate the socket where the microprocessor must be installed.
	7. Align the notch on the microprocessor with the alignment notch on the motherboard.
	8. Gently place the microprocessor in the socket.
	9. Use force to press the microprocessor firmly in the socket keeping in mind that no damage is caused to the pins. The microprocessors for Pentium II, Pentium III, and Celeron are available a card with the microprocessor installed on it. To install these microprocessors, we must fix the card holding the microprocessor in the slot on the motherboard.
	The microprocessors for Pentium II, Pentium III, and Celeron are available a card with the microprocessor installed on it. To install these microprocessors, we must fix the card holding the microprocessor in the slot on the motherboard.
	Hands on exercise
	To install the processor in the slot:
	1. Check the voltage requirements from the motherboard and the microprocessor documentation.
	2. Wear an anti-static wristband.
	3. Place the motherboard on the work desk.
	4. Locate the slot where the microprocessor must be installed
	5. Affix the plastic retention brackets on the motherboard, if not already installed.
	6. Take the microprocessor out of the anti-static bag.
	7. Hold the microprocessor perpendicular to the motherboard over the slot.
	8. Align the microprocessor with the plastic retention brackets.
	9. Slide the processor carefully in the motherboard slot
	10. Pull the lever on the microprocessor outward, if required, to lock the microprocessor to the plastic retention brackets
2.7 Configuring the Microprocessor
	The motherboard usually auto-detects the microprocessor. We can also configure the microprocessor by adjusting the jumper settings. Microprocessors can also be configured using the settings from the system Basic Input Output System (BIOS). The BIOS stores the system information.
	2.7.1 Speed of the Microprocessor
	The microprocessor is built and set to perform at the recommended speed. The recommended speed of the microprocessor is set below the maximum speed of the microprocessor. To modify the speed of the microprocessor using the system BIOS:
	1. Start the system.
	2. Press the Delete key on the keyboard to enter the BIOS setup.
	3. Select CPU PnP from the displayed menu using the navigations keys specified besides the menu.
	4. Press Enter to display CPU PnP setup screen that enables to modify the settings for the microprocessor.
	5. Use the Page Up or Page Down key on the keyboard to select the required CPU Ratio. The CPU ratio is a multiplier that sets the microprocessor clock speed.
	6. Press Esc to return to the BIOS main menu.
	7. Press F10 to save and exit.
	2.7.2 Overclocking
	Overclocking the microprocessor increases the speed of the processor. You can overclock the microprocessor by changing the jumper settings on the motherboard. You can also overclock the microprocessor by increasing the CPU Ratio from the CPU PnP Setup Page from the BIOS settings. Additional cooling devices such as CPU fans must be installed to cool down the processor because overclocking makes the microprocessor heat up very fast. The extreme heat level can reduce the life of the processor and can also damage the processor. Overclocking must be implemented with care by increasing the clock speed little by little. You must also check the documentation of the microprocessor and the motherboard before overclocking. Overclocking a processor beyond its maximum capacity can permanently damage the microprocessor.
2.8 Upgrading the Microprocessor
	The speed and the performance of microprocessors increase with the release of new processor. Besides this, every microprocessor has its own limitation. To keep the system up-to-date and to remove the limitations of the microprocessor, we must upgrade the microprocessor. To upgrade a microprocessor, we replace the microprocessor in the system with a new compatible microprocessor.
2.9 Troubleshooting Microprocessors
	Troubleshooting microprocessor techniques solve the problems that arise due to the improper functioning of the microprocessor. The general problems that arises from the microprocessor are overheating and slow processing.
	2.9.1 Overheating
	A microprocessor produces heat while processing the data. The microprocessor also overheats when it is performing beyond the recommended speed. Overheating can cause permanent damage to the microprocessor. Adequate cooling devices, such as a processor fan must be installed to cool down the microprocessor.To solve the problem of overheating :
	1. Check that the processor fan is installed and functioning properly.
	2. Check the jumper settings on the motherboard and the BIOS settings to see that the microprocessor is not overclocked.
	3. Check that the voltage supplied by the motherboard is compatible with the microprocessor.
	4. Check the motherboard manual to see that the motherboard supports the microprocessor.
	2.9.2 Slow Processing
	The microprocessor generally runs slow if there is some fault within it. A microprocessor can also run slow if the speed settings are not correct or due to some other fault in the system. To solve the problem of slow processing :
	1. Check if the vendor has supplied the correct microprocessor.
	2. Check if the microprocessor supports the applications that are running.
	3. Scan the computer for viruses.
	4. Check the jumper settings on the motherboard and the BIOS settings of the microprocessor.
	5. Troubleshoot the RAM.