Computer Hardware

Prof. Henry Martínez Miranda

Computer Repair Course

Computer Hardware

PCs, like the one above, are a general purpose tool with many parts.

Motherboard

A typical motherboard contains areas for computer memory, CPU, AGP, PCI and more.

Motherboard

Motherboards tie everything in your computer together.

Motherboard

Socket

Current socket arrangements are often named for the number of pins in the PGA. Commonly used sockets are:

• Socket 478 - for older Pentium and Celeron processors • Socket 754 - for AMD Sempron and some AMD Athlon

processors • Socket 939 - for newer and faster AMD Athlon

processors • Socket AM2 - for the newest AMD Athlon processors • Socket A - for older AMD Athlon processors

Anyone who already has a specific CPU in mind should select a motherboard based on that CPU.

Socket 754 ZIF

A Socket 754 motherboard

Socket 939 ZIF

A Socket 939 motherboard

Socket LGA755

The newest Intel CPU does not have a PGA. It has an LGA, also known as Socket T. LGA stands for Land Grid Array. An LGA is different from

a PGA in that the pins are actually part of the socket, not the CPU.

Motherboard Slots

Computer hardware, such as memory, PCI and AGP connect to the motherboard through slots.

The Chipset

The chipset is the "glue" that connects the microprocessor to the rest of the motherboard and therefore to the rest of the computer. On a PC, it consists of two basic parts --

the north bridge and the south bridge.

Buses

A bus is simply a circuit that connects one part of the motherboard to another. The more data a bus can handle

at one time, the faster it allows information to travel.

Motherboard Ports

Back Panel Connectors

Memory (RAM)

Computer memory has a big effect on system performance. Pictured above is SIMM memory, or single in-line memory module, which is a type

of RAM memory module.

DIMM Memory

DIMM, or dual in-line memory module, has a 64-bit path to memory chips, whereas the SIMM has only a 32-bit

(184-pin DDR DIMM RAMin the photo)

SODIMM Memory

SODIMM, or small outline dual in-line memory module, is made with integrated circuits and is about half the size of

DIMM modules. (200-pin DDR SODIMM RAM in the photo)

RAM Upgrade

A RAM upgrade can greatly extend your computer's lifespan.

BIOS

The basic input-output system BIOS is the first thing you see when you turn on your computer.

Microprocessor (CPU)

A microprocessor -- also known as a CPU or central processing unit -- is a complete computation engine that

is fabricated on a single chip.

Microprocessor (CPU)

64-bit processors have entered the mainstream, such as this eight-generation Athlon processor.

Hard disk

A hard disk is a sealed aluminum box, which has been opened in this photo. The controller electronics are

attached to one side, controlling the read/write mechanism and the motor that spins the platters.

Hard disk

This hard drive has three platters, also called hard disks, and six read/write heads.

Hard disk

The arm on a hard disk holds the read/write heads and has to be incredibly fast and precise. There is one arm per read/write head, and all of them

are lined up to form one unit.

Storing the Data

Data is stored on the surface of a platter in sectors and tracks. Tracks are concentric circles, and sectors are

pie-shaped wedges on a track.

IDE Interface

The Integrated Drive Electronics interface was the most popular way to connect a hard drive to a PC.

SATA (Serial ATA) Interface

• Serial ATA (SATA) hard drives have become the new standard in hard drive technology.

• SATA hard drives result in less clutter and increased airflow in the computer system, because SATA cables are dramatically narrower than EIDE cables.

PCI

The Peripheral Component Interconnect (PCI) bus provides direct access to system memory for connected devices. PCI slots can be used for

network, graphics and sound cards.

PCI

PCI cards use 47 pins to attach to a PCI slot. Pins are thin metal feet that allow computer chips to

be attached to a circuit board.

PCI Sound Card

A sound card allows a computer to create and record real, high-quality sound.

AGP

An AGP, or accelerated graphics port, allows the operating system to designate RAM for use by

the graphics card (like the one above) on the fly.

AGP

Like a motherboard, a graphics card is a printed circuit board that houses a processor and RAM.

PCI Express

PCI Express or PCIe eliminates the need for the AGP by accepting more data and supplying

more power to video cards.

USB

Just about any computer that you buy today comes with Universal Serial Bus connectors let

you attach everything from mice to printers.

Power Supply

PC power supplies use switcher technology to convert the AC input to lower DC voltages. The 3.3- and 5-volts are typically used by digital circuits, while the 12-volt is used

to run motors in disk drives and fans.

Power Supply

This PC power supply has been removed from its PC case. The small, red switch at right, above the power-cord connector, is for changing line

voltages in various countries.

Power Supply

In this photo you can see three small transformers (yellow) in the center. To the left are two

cylindrical capacitors. The large finned pieces of aluminum are heat sinks.

Laptops

Laptops are different from desktops only in how the components are put together.

Laptops

Because of this fundamental design difference and because of a laptop's inherent portability, components have to:

• Fit into a compact space • Conserve power • Produce less heat than desktop components

Laptops CPU

• Runs at a lower voltage and clock speed • Mounts to the motherboard without using pins • Has a sleep or slow-down mode

Laptop Heat Sink and Fan

Laptops usually have small fans, heat sinks, heat spreaders or heat pipes to help dissipate the

heat from the CPU.

Laptop Heat Sink and Fan

Here you can see a heat sink and fan in a laptop, similar to the hardware in a desktop.

Laptops Memory

Lapto ps often use smaller memory modules to save space. Memory types used in laptops include:

• Small Outline Dual Inline Memory Module (SODIMM) • Dual Data Rate Synchronous RAM (DDR SDRAM) • Single data rate Synchronous RAM (SDRAM) • Proprietary memory modules

A graphics processing unit (GPU)

Most laptops have graphics capability built into the motherboard or have smaller graphics cards with

a GPU designed specifically for laptop use.

Laptop LCD Screen

A laptop displays its graphics on a liquid crystal display (LCD) screen. Most screens measure between 12 and 17 inches, and the size of the screen affects the overall size of the laptop.

Laptop Battery

LiIon batteries are the current standard for laptop computers. They are light and have long life spans. They

do not suffer from the memory effect, can be charged randomly, and won't overheat if overcharged. They are also thinner than any other battery available for laptops, making them ideal for the new ultra-thin notebooks. LiIon batteries can last for anything from about 950 up to 1200

charges.