CPUs and motherboards Unit objectives Describe features and functions of CPUs, classify CPUs according to their specifications, and replace a CPU Describe the techniques used to cool CPUs and other components in a PC, and replace a system fan Describe motherboards, their components, and form factors, and replace a motherboard Identify the symptoms of, probable causes of, and potential solutions to problems with motherboards and CPUs

Topic A Topic A: Central processing units Topic B: Cooling techniques Topic C: Motherboards Topic D: Motherboard and CPU troubleshooting

Central processing unit (CPU) “Brains” of your PC Processes instructions, manipulates data, controls interactions of other circuits Contains: –A control unit –One or more execution units –Single-core vs. multi-core processors –Registers

CPU performance Instruction — Low-level, hardware- specific command Rated in millions of instructions per seconds (MIPS) Rated according to clock speed Older CPUs — One clock cycle/ one instruction Newer CPUs — One clock cycle/ many instructions

CPU design characteristics Addressable RAM Branch prediction Address bus Data bus Internal bus Cache Clock speed Dual Independent Bus (DIB) Front-side bus speed continued

CPU characteristics, continued Hyperthreading Multimedia extensions (MMX) Multiprocessing Out-of-order completion Overclocking Pipelining Register renaming Single Instruction Multiple Data (SIMD) continued

CPU characteristics, continued Speculative execution Superpipelining Superscalar Throttling

Multiple-processor support Requires symmetric multiprocessing code for OS and applications Symmetric multiprocessing code is included in: –Windows 2000 Professional –Windows XP Professional –Windows Vista Business, Ultimate, Enterprise –32-bit versions of Windows 7 Linux and Linux applications are available in symmetric multiprocessing versions 64-bit versions of Windows 7 use NUMA

Processor specifications Manufacturers: –Intel –AMD –Centaur Technology –Elbrus International –Integrated Device Technology, Inc. (IDT) –SIS (Silicon Integrated Systems) –ST Microelectronics Primary specifications Bus width specifications Internal specifications

Activity A-1 Identifying CPUs

Inside the case Chipsets CPU packaging Slots Cooling techniques

Chipsets Memory control System bus functions Audio functions Video display functions System management functions

Northbridge and Southbridge Two most important components of a PC chipset Northbridge controls interactions between the CPU, memory, AGP video control circuitry, and the Southbridge continued

Northbridge/Southbridge, continued Southbridge controls interactions between buses and devices not controlled by the Northbridge –PCI expansion bus –Floppy drive controller –Serial port –Parallel port –PS/2 keyboard and mouse ports

CPU packaging Chip = die A package is made up of –Die –Plastic, metal, or ceramic case –Wires or connectors –Support chips –Cooling components

PGA package 80486

SECC package Pentium 3

Packages continued

Packages, continued continued

Packages, continued continued

Packages, continued

Sockets and slots continued

Sockets and slots, continued continued

Sockets and slots, continued

Pentium with MMX CPU & Socket 7 socket

Activity A-2 Identifying your CPU’s socket and package type

CPU installation CPU typically replaced as part of new motherboard Add another CPU to multiprocessor motherboard CPU packaging must match slot or socket in motherboard CPU packages held in place by retaining clips, locking lever, or other mechanism

CPU retaining clips

Installing a CPU 1.Unplug the computer and open the case 2.Remove the old CPU 3.Store the old CPU 4.Insert the new CPU package into its socket and secure it with the retaining mechanism 5.Close the case, reconnect cables, and boot the PC

Activity A-3 Replacing a CPU (optional)

Topic B Topic A: Central processing units Topic B: Cooling techniques Topic C: Motherboards Topic D: Motherboard and CPU troubleshooting

Typical cooling mechanisms Fans Heat sinks and cooling fins Heat pipes Water pumps Peltier coolers Undervolting

Power supply and CPU fans Power supply fan CPU fan

Cooling fins

Cooling fins and a fan

Other cooling techniques Heat pipes — Small tubes filled with fluid Water pumps — Tubes filled with water, moved away from CPU to outside case and through cooling fins Peltier coolers –Electronic device that gets colder when voltage is applied –Non-convection –Connected directly to CPU –Can be combined with water coolers continued

Other cooling techniques, continued Phase-change cooling –Vapor compression –Gas to liquid –Liquid absorbs processor heat and evaporates –Gas returned to compressor –Cycle begins again –More efficient than water cooling systems –Generate significant noise Undervolting –Less power; less heat –Can cause system problems

Activity B-1 Examining the cooling systems in your PC

Activity B-2 Replacing a system fan

Topic C Topic A: Central processing units Topic B: Cooling techniques Topic C: Motherboards Topic D: Motherboard and CPU troubleshooting

A motherboard Main circuit board

Motherboards Components review CPU Expansion slots Graphics adapter slot Hard drive interface connectors Floppy drive interface connector Optical drive interface connector Power connector Memory slots PS/2 mouse and keyboard ports USB port IEEE 1394 / FireWire port Serial port Parallel port Battery Network interface and modem Video connectors

Daughter board A circuit board Connects to another circuit board to provide or assist with its functions Most often used with video cards

Riser card Riser card with expansion slots Motherboard Connector between the two

Form factor Size and shape of a motherboard Dictates power supply and case Describes physical layout of components

Activity C-1 Examining motherboard components and form factor

Motherboard installation Failures from manufacturing defects or rough handling Replaced due to failure; upgrades; building PC from scratch Held in place by screws or plastic clips Remove wires, cables, connectors, and other system components, such as power supply and drives

Installing a motherboard 1.Unplug the computer and open the case 2.Disconnect all wires from old motherboard 3.Remove the power supply and drives 4.Remove the old motherboard 5.Store the old motherboard 6.Install the new motherboard 7.Reinstall the power supply and drives 8.Connect all wires 9.Close the case, reconnect cables, and boot the PC

Activity C-2 Replacing a motherboard (optional)

Topic D Topic A: Central processing units Topic B: Cooling techniques Topic C: Motherboards Topic D: Motherboard and CPU troubleshooting

Motherboard and CPU problems System fails to boot Burning or foul odor or smoke comes out of the case Fans come on and power lights indicate that power is present, but system fails to boot Video display problems occur on system with integrated display adapter Intermittent problems occur that can’t be traced to failure of other components

Activity D-1 Troubleshooting motherboard and CPU problems

Unit summary Described features and functions of CPUs, classified CPUs according to their specifications, and replaced a CPU Described the techniques used to cool CPUs and other components in a PC, and replaced a system fan Described motherboards, their components, and form factors, and replaced a motherboard Identified the symptoms of, probable causes of, and potential solutions to problems with motherboards and CPUs