Introduction to Personal Computer Hardware

SATA keyed connector

-Connects Disk Drives -Connector is wider and thinner than a Molex connector

How many volts before it hurts?

10,000 volts

BD

25 GB SL and 50 GB DL ROM -R -RE

How many volts of electricity are needed for a person to feel an electric shock?

3,000 volts of static electricity

What are the most common voltages supplied in a power supply?

3.3 volts, 5 volts, and 12 volts. The 3.3 volt and 5 volt supplies are typically used by digital circuits, while the 12 volt supply is used to run motors in disk drives and fans.

This connector has two rows of three to four pins and -supplies power to internal components.

6/8- pin PCIe power connector.

Axillary power connectors

A 4- pin connector which has two rows of two pins and an 8-pin connector which has two rows with four pins each. These connectors supply power to different areas of the motherboard. The auxiliary power connector is the same shape as the main power connector but smaller.

Chipset

A group of chips on the motherboard that controls the timing and flow of data and instructions to and from the CPU.

KVM Switch

A keyboard, video, and mouse (KVM) switch is a hardware device that can be used to control more than one computer while using a single keyboard, monitor, and mouse. For businesses. KVM switches provide cost-efficient access to multiple servers. Home users can save space using a KVM switch t connect multiple computers to one keyboard, monitor, and mouse, Some KVM switches have the capability to share USB devices and speakers with multiple computers.

Network

A network port, also known as an RJ-45 or 8P8C port has 8 pins and connects devices to a network, The connection speed depends on the type of network port. The maximum length of the Ethernet network cable is 100 m (328 ft.).

Video Ports and Cables

A video port connects a monitor cable to a computer. Video ports and monitor cables transfer analog signals, digital signals, or both. Computers are digital devices that crate digital signals. The digital signals are sent to the graphics card where they are transmitted through a cable to a desplay.

Wireless NIC

A wireless NIC connects a computer to a network using radio frequencies.

This is the only choice that does not allow for +3.3 V.

AT.

This is the most common power supply on the market today. It includes a second motherboard connector to provide dedicated power to the CPU. There are several versions available.

ATX12V

Adapter Cards

Adapter cards increase the functionality of a computer by adding controllers for specific devices or by replacing malfunctioning ports.

eSATA card

Adds additional internal and external SATA ports to a computer through a single PCI Express slot.

What are the various computer desktop power supply form factors that that have evolved over time.

Advanced Technology (AT) - This is the original power supply for legacy computer systems now considered obsolete. AT Extended (ATX) - This is the updated version of the AT but still considered to be obsolete. ATX12V - This is the most common power supply on the market today. It includes a second motherboard connector to provide dedicated power to the CPU. There are several versions of ATX12V available. EPS12V - This was originally designed for network servers but is now commonly used in high-end desktop models.

ATX

Advanced Technology Extended This is the most common motherboard form factor. This case accommodates the integrated I/O ports on the standard ATX motherboard. The ATX power supply connects to the motherboard via a single 20-pin connector.

Southbridge

Allows the CPU to communicate with slower speed devices including hard drives, Universal Serial Bus (USB) ports, and expansion slots

Audio and Game Port

Audio ports connect audio devices to the computer. Analog ports typically include a line in port to connect to an external source, a microphone port, and line out ports to connect speakers or headphones, The game port connects to a joystick or MIDI-interfaced device.

Basic input/output system (BIOS) chip and Unified Extensible Firmware Interface (UEFI) chip

BIOS is used to help boot the computer and manage the flow of data between the hard drive, video card, keyboard, mouse, and more. In modern computers BIOS has been replaced by UEFI. UEFI specifies a different firmware for boot and runtime services. Firmware is programming that allows a computer operating system to control the hardware.

Central Processing Unit (CPU)

Brain of the computer that performs instructions defined by software

DVD

Capacity 4.7 SL and 8.5 GD DL ROM +/-R +/-RW

CD

Capacity of 700 MB ROM R RW

Motherboard components

Chipsets ■ Expansion slots and buses ■ Memory slots and external cache ■ CPUs and their sockets ■ Power connectors ■ Onboard disk drive connectors ■ Keyboard connectors ■ Integrated peripheral ports and headers ■ BIOS/firmware ■ CMOS battery ■ Front‐panel connectors

Types of Optical Storage Devices

Compact Disc (CD) - audio and data Digital Versatile Disc (DVD) - digital video and data Blu-ray Disc (BD) - HD digital video and data

Cooling Systems

Computers are kept cool using active and passive cooling solutions. Active solutions require power while passive solutions do not. Passive solutions for cooling usually involve reducing the speed at which a component is operating or adding heat sinks to computer chips. A case fan is considered as active cooling. The figure shows examples of passive and active cooling solutions.

MOLEX keyed connector.

Connects hard drives, optical drives, or other devices.

Northbridge

Controls high speed access to the RAM and video card. It also controls the speed at which the CPU communicates with all of the other components in the computer. Video capability is sometimes integrated into the Northbridge.

DDR SDRAM

DDR SDRAM transfers data twice as fast as SDRAM; Able to support two writes and two reads per CPU clock cycle; Connector has 184 pins and a single notch; Uses lower standard voltage (2.5 V); Family: DDR2, DDR3, DDR4.

DDR2 SDRAM

DDR2 SDRAM also transfers data twice as fast as SDRAM; Runs at higher clock speeds than DDR (553 MHz vs. DDR at 200 MHz); Improves performance by decreasing noise and crosstalk between signal wires; Connector has 240 pins; Uses lower standard voltage (1.8 V).

DDR3 SDRAM

DDR3 SDRAM expands memory bandwidth by doubling the clock rate of DDR2; Consumes less power than DDR2 (1.5 V); Generates less heat; Runs at higher clock speeds (up to 800 MHz); Connector has 240 pins.

DDR4 SDRAM

DDR4 SDRAM quadruples DDR3 maximum storage capacity; Consumes less power than DDR3 (1.2 V); Runs at higher clock speeds (up to 1600 MHz); Connector has 288 pins; Available with advanced error correction features such as error-correcting code memory (ECC memory) to detect multiple bit errors.

SDRAM

DRAM that operates in synchronization with the memory bus; Able to process overlapping instructions in parallel - e.g. It can process a read before a write has been completed; Higher transfer rates.

Storage Devices

Data drives provide non-volatile storage of data, meaning that when the drive loses power, the data is retained and available the next time the drive is powered on.

DVI

Digital Visual Interface The DVI connector is usually white and consists of as many as 24 pins (3 rows of 8 pins) for digital signals, up to 4 pins for analog signals, and a flat pin called a ground bar.

SSDs come in three form factors:

Disc drive form factor - These are similar to an HDD in which the semiconductor memory is in a closed package that can be mounted in computer cases like an HDD. They can be 2.5, 3.5, and 1.8 inches, although those are rare. Expansion cards - This plugs directly into the motherboard and mounts in the computer case like other expansion cards. mSata or M.2 modules - These packages may use a special socket. M.2 is a standard for computer expansion cards. It is a family of standards that specify physical aspects of expansion cards such as connectors and dimension.

DisplayPort

DisplayPort is an interface technology that is designed to connect high-end graphics-capable PCs and displays, as well as home theater equipment and displays.

DIMM Memory

Dual Inline Memory Module is a circuit board that holds SDRAM, DDR SDRAM, DDR2 SDRAM, DDR3 SDRAM, and DDR4 SDRAM chips. There are 168-pin SDRAM DIMMs, 184-pin DDR DIMMs, 240-pin DDR2 and DDR3 DIMMs, and 288-pin DDR4 DIMMs

DIP

Dual Inline Package is an individual memory chip. A DIP has dual rows of pins used to attach it to the motherboard.

EPS12V

EPS12V power supply that was originally designed for network server, but is now commonly used in high-end desktop models

This was originally designed for network servers but is now commonly used in high-end desktop models

EPS12V.

ESD

Electrostatic discharge (ESD) can occur when there is a buildup of an electric charge (static electricity) that exists on a surface which comes into contact with another, differently charged surface. ESD can cause damage to computer equipment if not discharged properly.

EPROM

Erasable programmable read-only memory is non-volatile but can be erased by exposing it to strong ultraviolet light. EPROMs usually have a transparent quartz window on the top of the chip. Constant erasing and reprogramming could ultimately render the chip useless.

Hard Disk Drive (HDD)

HDDs are the traditional magnetic disk devices that have been used for years. Their storage capacity ranges from gigabytes (GBs) to terabytes (TBs). Their speed is measured in revolutions per minute (RPM). This indicates how fast the spindle turns the platters that hold the data. The faster the spindle speed, the faster a hard drive can find data on the platters. This can correspond to faster transfer speeds. Common hard drive spindle speeds include 5400, 7200, 10,000, and 15,000 RPM. HDDs come in 1.8, 2.5 and 3.5 inch form factors, as shown in Figure 1. The 3.5 inch form factor is standard for personal computers. 2.5 inch HDDs are typically used in mobile devices. 1.8 inch HDDs were used in portable media players and other mobile applications, but are seldom used in new devices.

HDMI

High-Definition Multimedia Interface HDMI was developed specifically for high-definition televisions. However, its digital features also make it a good candidate for computers.

Why must electrical equipment be grounded?

If a fault causes metal parts of the equipment to become live with electrical current, the ground will provide a path of least resistance for the current to flow harmlessly away. Typically computer product connect to ground via the power plug. Large equipment such as server racks that house network devices must also be grounded.

Land Grid Array (LGA)

In an LGA architecture, the pins are in the socket instead of on the processor.

EEPROM

Information is written to an electrically erasable programmable read-only memory chip after it is manufactured and without removing it from the device. EEPROM chips are also called Flash ROMs since its contents can be "flashed" for deletion. EEPROMs are often used to store a computer system's BIOS.

The Original Input Devices

Input devices allow the used communicate with a computer. The images below are some of the first input devices.

Other Ports and Cables

Input/output (I/O) ports on a computer connect peripheral devices such as printers, scanners, and portable drives. In addition to the ports and interfaces previously discussed, a computer may also have other ports.

IDE

Integrated Drive Electronics The IDE cable is a ribbon cable used to connect storage drives inside the computer. The 2 most common types of IDE ribbon cables are the 34-pin cable used for floppy drives and the 40-pin cable for hard drives and optical drives.

Storage Device Interfaces

Internal storage devices often connect to the motherboard using Serial AT Attachment (SATA) connections. The SATA standards define the way that data is transferred, the transfer rates, and physical characteristics of the cables and connectors.

Recommendations to help prevent ESD damage.

Keep all components in antistatic bags until you are ready to install them. Use grounded mats on workbenches. Use grounded floor mats in work areas. Use antistatic wrist straps when working inside computers.

Tape Drive

Magnetic tapes are most often used for archiving data. At one time they were useful for backing up PCs, however as HDDs became cheaper, external HDD drives are now frequently used for this purpose. However, tape backups are still used in enterprise networks. Tape drives use a magnetic read/write head and removable tape cartridge, as shown in Figure 2. Although data retrieval using a tape drive can be fast, locating specific data is slow because the tape must be wound on a reel until the data is found. Common tape storage capacities vary between a few GBs to many TBs.

This connects hard drives, optical drives, or other devices.

Molex.

NIC

Network Interface Card (NIC) A NIC connects a computer to a network using a network cable.

NVMe

Non-Volatile Memory Express Developed specifically to allow computers to take greater advantage of the features of SSDs by providing a standard interface between SSDs, the PCIe bus, and operating systems. NVMe allows compliant SSD drives to attach to the PCIe bus without requiring special drivers, in much the same way that USB flash drives can be used in multiple computers without requiring installation on each.

Dynamic RAM

Older technology; popular until the mid-1990s; Used for main memory, DRAM gradually discharges energy so it must be constantly refreshed with pulses of electricity in order to maintain the stored data in the chip

PS/2

Personal System 2 A PS/2 port connects a keyboard or a mouse to a computer. The PS/2 port is a 6-pin mini-DIN female connector. The connectors for the keyboard and mouse are often colored differently. If the ports are not color coded, look for a small figure of a mouse or keyboard next to each port.

What are the different power supplies?

Power supplies can also be single rail, dual rail, or multi rail. A rail is the printed circuit board (PCB) inside the power supply to which the external cables are connected. A single rail has all of the connectors connected to the same PCB while a multi rail PCB has separate PCBs for each connector.

Universal Serial Bus (USB) controller card

Provides additional USB ports to connect the computer to peripheral devices.

RCA

Radio Corporation of America RCA connectors have a central plug with a ring around it and are used to carry audio or video. RCA connectors are often found in groups of 3, where a yellow connector carries video and a pair of red and whit connectors carries left and right audio channels.

RAM

Random Access Memory A temporary location to store data and applications

RAM

Random Access Memory RAM is the temporary working storage for data and programs that are being accessed by the CPU. Unlike ROM, RAM is volatile memory, which means that the contents are erased every time the computer is powered off. Adding more RAM in a computer enhances the system performance. For instance, more RAM increases the memory capacity of the computer to hold and process programs and files. With less RAM, a computer must swap data between RAM and the much slower hard drive. The maximum amount of RAM that can be installed is limited by the motherboard.

ROM

Read-Only Memory An essential computer chip is the read-only memory (ROM) chip. ROM chips are located on the motherboard and other circuit boards and contain instructions that can be directly accessed by a CPU. The instructions stored in ROM include basic operation instructions such as booting the computer and loading the operating system. ROM is nonvolatile which means that the contents are not erased when the computer is powered off.

ROM

Read-only memory chips. Information is written to a ROM chip when it is manufactured. A ROM chip that cannot be erased or re-written is now obsolete. The term ROM still tends to be used generically for any read-only memory chip type.

Magnetic Data Storage Devices

Records bits as magnetized areas on a magnetic media. HDD Tapes

Magnetic

Records bits as magnetized areas on magnetic media. HDD Tape Drive

Static RAM

Requires constant power to function; Often used for cache memory; Uses lower power consumption; Much faster than DRAM; More expensive than DRAM.

SATA

Serial Advanced Technology Attachment The SATA cable connects SATA devices to the SATA interface using a 7-[in data cable. SATA connectors have an L-shaped slot so the cable only fits in one orientation. This cable does not supply any power to the SATA device. A separate power cable; provides power to the drive.

SIMM

Single Inline Memory Module is a small circuit board that holds several memory chips. SIMMs have 30-pin or 72-pin configurations.

SODIMM

Small Outline DIMM has a 72-pin and 100-pin configurations for support of 32-bit transfers or a 144-pin, 200-pin, 204-pin, and 260-pin configurations for support of 64-bit transfers. This smaller, more condensed version of DIMM provides random access data storage that is ideal for use in laptops, printers, and other devices where conserving space is desirable.

Berg keyed connector.

Smaller that a MOLEX connector and connects to legacy floppy drives.

What is a compromise between a magnetic HDD and a SSD?

Solid State Hybrid Drives (SSHDs) are a compromise between a magnetic HDD and an SSD. They are faster than an HDD but less expensive than an SSD. They combine a magnetic HDD with onboard flash memory serving as a non-volatile cache. The SSHD drive automatically caches data that is frequently accessed, which can speed up certain operations such as operating system start up.

Semiconductor Storage

Solid-state drives (SSD) store data as electrical charges in semiconductor flash memory. This makes SSDs much faster than magnetic HDDs. SSD storage capacity ranges from around 120 GBs to many TBs. SSDs have no moving parts, make no noise, are more energy efficient, and produce less heat than HDDs. Because SSDs have no moving parts to fail, they are considered to be more reliable than HDDs.

Sound adapter

Sound adapters provide audio capability.

Random Access Memory (RAM)

Temporary memory a computer uses to store information while it is processing.

GDDR SDRAM

The "G" stands for Graphics; RAM specifically designed for video graphics; Used in conjunction with a dedicated GPU; Family: GDDR, GDDR2, GDDR3, GDDR4, GDDR5; Each family member improves performance; Each family member lowers power consumption; GDDR SDRAM processes massive amounts of data but not necessarily at the fastest speeds.

ITX

The ITX form factor has gained in popularity because of its very small size. There are many types of ITX motherboards; however, Mini-ITX is one of the most popular. The Mini-ITX form factor uses very little power, so fans are not needed to keep it cool. A Mini-ITX motherboard has only one PCI slot for expansion cards. A computer based on a Mini-ITX form factor can be used in places where it is inconvenient to have a large or noisy computer.

USB

The Universal Serial Bus USB is a standard interface that connects peripheral devices to a computer. USB devices are ho=swappable, which means that used can connect and disconnect the devices while the computer is powered on.

Motherboard Form Factors

The form factor of motherboards pertains to the size and shape of the board. It also describes the physical layout of the different components and devices on the motherboard.

Motherboards

The motherboard, also known as the system board or the main board, is the backbone of the computer. As shown in the figure, a motherboard is a printed circuit board (PCB) that contains buses, or electrical pathways, that interconnect electronic components. These components may be soldered directly to the motherboard, or added using sockets, expansion slots, and ports.

Adapters and Cables

There are many connection standards in use today. Many are interoperable but require specialized components. These components are called adapters and converters.

Disc drive form factor

These are similar to an HDD in which the semiconductor memory is in a closed package that can be mounted in computer cases like an HDD. They can be 2.5, 3.5, and 1.8 inches, although those are rare.

What do connectors do?

These connectors are used to power various internal components such as motherboards and disk drives. Connectors are keyed which is a type of design that can only be inserted in one direction.

A 20-pin with two rows of 10 pins each and a 24 pin slotted connector with two rows of 12 pins each.

These connectors connect to the motherboard

mSata or M.2 modules

These packages may use a special socket. M.2 is a standard for computer expansion cards. It is a family of standards that specify physical aspects of expansion cards such as connectors and dimension.

Expansion Slots and Cards

These provide locations to connect additional components.

Capture card

These provide the ability to watch and record television signals on a PC by connecting a cable television, satellite, or antenna to the installed tuner card.

USB to PS/2 adapter

This adapter is used to connect a USB keyboard to connect a USB keyboard to mouse to a PS/2 port.

DVI to VGA adapter

This adapter is used to connect a VGA cable to a DVI port.

DVI to HDMI adapter

This adapter is used to connect an HDMI monitor to a DVI port.

PCLe 6/8 pin power connector.

This connector has two rows of three to four pins and supplies power to internal components. Serial Advanced Technology Attachment (SATA)

USB-to-Ethernet Converter

This converter USB to an Ethernet.

HDMI yo VGA Converter

This converter is used to convert VGA signals to HDMI signals.

Adapters

This is a component that physically connects one technology to another. For ei, a DVI to HDMI adapter. The adapter could be one component or a cable with different ends.

VGA

This is a connector for analog video. It has 3 rows and 15 pins. It is also sometimes referred to as the DE-15 or HD-15 connector.

Micro-ATX

This is a smaller form factor that is designed to be backward-compatible with ATX. Micro-ATX boards often use the same Northbridge and Southbridge chipsets and power connectors as full-size ATX boards and therefore can use many of the same components. Generally, Micro-ATX boards can fit in standard ATX cases. However, Micro-ATX motherboards are much smaller than ATX motherboards and have fewer expansion slots.

Molex to SATA adapter

This is used to connect a STA drive to a Molex power cable.

Converter

This performs the same function as an adapter but also translates the signals from one technology to to the other. For ei, a USB 3.0 to SATA converter enable a hard disk drive to be used as a flash drive.

Expansion cards

This plugs directly into the motherboard and mounts in the computer case like other expansion cards.

Antistatic wrist strap

This should be attached to you when working inside computers.

Thunderbolt 3

Thunderbolt 3 uses the same connector as USB-C. It has twice the bandwidth of Thunderbolt 2, uses less power, and can provide two 4K monitors with video.

Thunderbolt 1 or 2

Thunderbolt allows for high-speed connection of peripherals such as hard drives, RAID arrays, network interfaces, and it can transmit high definition video using the the DisplayPort protocol.

Static Electricity

Tis is a buildup of an electric charge that exists on a surface which comes in to contact with another, differently charged surface.

Optical Data Storage Devices

Uses light to record or read data. CD DVD Blu-ray

Optical

Uses light to record or read data. CD DVD Blu-ray

Solid State Data Storage Devices

Uses non-volatile memory chips to store data. Flash Drive 2.5" SSD

Solid State

Uses non-volatile memory chips to store data. 2.5" SSD Flash Drive

Video adapter

Video adapters provide video capability.

motherboard

a printed circuit board that contains busses, or electrical pathways, that interconnects electronic components

Northbridge

controls high speed access to the RAM and video card

What is a CPU?

he central processing unit (CPU) is responsible for interpreting and executing commands. It handles instructions from the computer's other hardware, such as a keyboard, and software. The CPU interprets the instructions and outputs the information to the monitor or performs the requested tasks.

What does a computer do?

input, process, output, storage

L1

internal cache that is integrated into the CPU

solutions to help prevent ESD damage

keep all components in antistatic bags; use grounded floor mats in work areas.

How many volts to fry a computer?

less than 30 volts of static electricity can damage a computer component.

ATX12V

most common power supply on market. It includes a second motherboard connector to provide dedicated power to the CPU.

pin grid array (PGA)

n PGA architecture, the pins are on the underside of the processor package and is inserted into the motherboard CPU socket using zero insertion force (ZIF). ZIF refers to the amount of force needed to install a CPU into the motherboard socket or slot.

What does the case of a desktop computer house?

power supply, motherboard, central processing unit (CPU), memory, disk drives, and assorted adapter cards.

PROM

programmable read-only memory Information on a programmable read-only memory chip is written after it is manufactured. PROMs are manufactured blank and then can be programmed by a PROM programmer when needed. Generally, these chips cannot be erased and can only be programmed once.