Computer Maintenance - Advanced Computer Hardware

Game Port

15-pin game port on a computer, used as a connector for joystick input. Originally located on a dedicated game controller expansion card and then later integrated with sound cards and on PC motherboards.

HDMI Port

A 19-pin connector for high definition interface between any audio and video source over a single cable.

DisplayPort

A 20-pin connector that transmits digital video and audio (not analog transmissions) and is slowly replacing VGA and DVI ports on personal computers. Also supports high-definition audio and video.

CGA (Color Graphics Adapter)

A Color Graphics Adapter Introduced by IBM in 1981. It is now obsolete.

Secure Boot

A UEFI feature that prevents a system from booting up with drivers or an OS that are not digitally signed and trusted by the motherboard or computer manufacturer.

shielded twisted pair (STP) cable

A cable that is made of one or more twisted pairs of wires and is surrounded by a metal shield.

Trusted Platform Module (TPM)

A chip on the motherboard of the computer that provides cryptographic services.

Graphics Processing Unit

A chip that performs the rapid mathematical calculations required to render graphics. Can be integrated or dedicated.

complementary metal-oxide semiconductor (CMOS)

A chip that retains system settings such as the time, keyboard settings, and boot sequence using a battery. However, if the battery fails, important settings can be lost. Therefore, it is recommended that BIOS settings always be documented.

Internal SCSI Cable

A common SCSI connector for internal hard drives. Has 50 pins arranged in two rows and is attached to a ribbon cable.

RJ-45

A connector that terminates the cable and is plugged into an Ethernet port and is used by twisted-pair cable to connect to a wired network adapter or other hardware device.

CPU Virtualization

A hardware feature supported by AMD and Intel CPUs that enables a single processor to act as multiple processors. Allows the operating system to support virtualization more effectively and efficiently than is possible through software emulation.

PS/2 port

A legacy 6 pin mini DIN connector used to connect a keyboard and mouse.

serial port

A male 9-pin or 25-pin port on a computer system. Was once used to connect various peripherals such as printers, scanners, and modems. but today is occasionally used for making console connections to network devices to perform initial configuration. Data travels serially, one bit at a time, through the port. Serial ports are sometimes configured as COM1, COM2, COM3, or COM4.

Current (amps)

A measure of the amount of electrons moving through a circuit per second

Power (watts)

A measure of the amount of work required to move electrons through a circuit (current x voltage)

Contrast ratio

A measurement of how white and how black a monitor can get.

USB Type-C

A new USB port that is a reversible plug connector, operates using USB 3.0, being used by Mac and ChromeBook. It also provides power, video output as well as data transfer. This type will eventually replace USB Type-A/Type-B plugs.

RJ-11

A phone line connection or port found on modems, telephones, and house phone outlets.

Audio Port

A port that connects audio equipment to the sound card of a computer to facilitate the exchange of data. Can be used by a microphone, audio in, audio out, and stereo audio out. Also called a sound port.

Program

A sequence of stored instructions that have been coded into something that can be run by a machine.

coaxial cable

A single copper wire surrounded by layers of plastic insulation and sheathing; used mainly in cable television and cable Internet service.

Mini-USB

A smaller type of USB, commonly used for cameras and external hard drives. This connector is being phased out in favor of Micro-USB.

CPU Throttling

A technique used when the processor runs at less than the rated speed to conserve power or produce less heat. Commonly used on laptops and other mobile devices.

VGA Port

A type of 15-pin three-row analog video port for connecting to an analog video display and is the oldest graphics port likely still used on some PCs, although it is quickly becoming a legacy technology.

RG-59

A type of coaxial cable characterized by a 75-ohm impedance and a 20 or 22 AWG core, usually made of braided copper. Less expensive but suffering greater attenuation than the more common RG-6 coax, typically used for short distance applications, such as carrying composite video between two nearby devices

Dual Voltage Power Supply

A type of power supply that has a switch that sets the input voltage to the power supply to either 110V / 115V or 220V / 230V.

USB Type-B

Accessory side plug type-USB. Typically used for printers and external drives.

UEFI/BIOS Password

Allows for different levels of access to the BIOS settings. Usually, there are two password settings that can be altered; the Supervisor Password and the User Password.

BIOS EEPROM

Allows the user to "flash" the BIOS without opening the computer case to update the BIOS firmware. Many motherboard manufacturers now provide software to flash the BIOS from within an operating system.

FHD (Full High Definition)

Also known as 1080p, Good setting for typical user.

QHD (Quad High Definition)

Also known as 1440p, suggested resolution for high-end users and gamers.

HD (High Definition)

Also known as 720p.

Case Fan

An active cooling solution uses fans inside of a computer case to blow out hot air. For increased air flow, some cases have multiple fans with cool air being brought in while another fan is blowing out hot air.

Lightning Connector

Apple proprietary connector, 8 pins, generally used to charge an Apple mobile device

Drive encryption

BIOS security method that allows software or hardware to secure every bit of data that goes onto a drive to prevent unauthorized access to data. Without the correct password, the computer cannot boot and data read from the hard drive cannot be understood. Even if the hard drive is placed in another computer, the data remains encrypted.

twisted-pair cable

Cables made of copper wires that are twisted around each other and are surrounded by a plastic jacket (such as traditional home phone wire). The twisting of wire pairs helps reduce crosstalk and electromagnetic induction. This is the most commonly used kind of networking cable today.

RG-6 Cable

Coaxial Cable used for connecting homes to cable networks. Larger conductor and higher frequencies than RG-59.

Blackout

Complete loss of AC power. A blown fuse, damaged transformer, or downed power line can cause a blackout.

BNC cable

Connect coaxial cables to devices using a quarter-turn connection scheme. Used with digital or analog audio, or video.

Interlaced scanning

Creates the image by scanning the screen two times. The first scan covers the odd lines, top to bottom, and the second scan covers the even lines.

Non-Interlaced scanning

Creates the image by scanning the screen, one line at a time from top to bottom.

DVI Port

Digital visual interface; another type of video port used to connect some monitors. Variants of the interface are configured to support multiple transmission modes. DVI-A (analog) supports analog only, DVI-D (digital) supports digital only, and DVI-I (integrated) supports both digital and analog. There are also two forms of connections; single-link connections that use a single Transition Minimized Differential Signaling (TMDS) transmitter, and dual-link connections that use two TMDS transmitters to provide higher-resolutions to larger monitors.

Power surge

Dramatic increase in voltage above the normal flow of electrical current. A power surge lasts for a few nanoseconds, or one-billionth of a second.

CPU Heatsink

Draws heat away from the CPU, which in turn the hot air is blown out by the case fan. Has a large surface area with metal fins to dissipate heat into the surrounding air.

Striping RAID

Enables data to be distributed across multiple drives. This provides a significant performance increase. However, since the data is distributed across multiple drives, the failure of a single drive means that all data is lost.

Refresh rate

Expressed in Hertz (Hz) and refers to how often per second the image is rebuilt

Surge protector

Helps protect against damage from surges and spikes. A surge suppressor diverts extra electrical voltage that is on the line to the ground. The amount of protection offered by a surge protector is measured in joules. The higher the joule rating, the more energy over time the surge protector can absorb. Once the number of joules is reached, the surge protector no longer provides protection and will need to be replaced.

Standby Power Supply (SPS)

Helps protect against potential electrical power problems by providing a backup battery to supply power when the incoming voltage drops below the normal level. The battery is on standby during normal operation. When the voltage decreases, the battery provides DC power to a power inverter, which converts it to AC power for the computer. This device is not as reliable as a UPS because of the time it takes to switch over to the battery. If the switching device fails, the battery cannot supply power to the computer.

Uninterruptible Power Supply (UPS)

Helps protect against potential electrical power problems by supplying a consistent level of electrical power to a computer or other device. The battery is constantly recharging while the UPS is in use. The UPS provides a consistent quality of power when brownouts and blackouts occur. Many UPS devices can communicate directly with the computer operating system. This communication allows the UPS to safely shut down the computer and save data prior to the UPS losing all battery power.

Noise

Interference from generators and lightning. Noise results in poor quality power, which can cause errors in a computer system.

Resolution

Measured by the number of horizontal and vertical pixels. e.g. 1920 x 1080 (i.e., 1080p)

MHz

Millions of cycles per second, a unit used to measure clock speed in computers.

eSATA adapter

Often, an expansion card is installed in the computer to provide eSATA ports.

Overclocking

Overclocking is a technique used to make a processor work at a faster speed than its original specification.

Unified Extensible Firmware Interface (UEFI)

Provides additional features and addresses security issues with legacy BIOS. Configures the same settings as traditional BIOS but also provides additional options. Can run on 32-bit and 64-bit systems, supports larger boot drives and includes additional features such as secure boot.

Parity RAID

Provides basic error checking and fault tolerance by storing checksums separately from data. This enables the reconstruction of lost data without sacrificing speed and capacity, like mirroring.

Double Parity RAID

Provides fault tolerance up to two failed drives.

Brownout

Reduced voltage level of AC power that lasts for a period of time. Brownouts occur when the power line voltage drops below 80 percent of the normal voltage level and when electrical circuits are overloaded.

Monitor resolution

Relates to the amount of information that can be displayed on a screen; Usually measured in pixels per inch.

Native resolution

Resolution of an LCD display that produces the best display quality.

LoJack

Security feature included in some BIOS/UEFI that enables a user to track the location of a stolen PC, install a key logger, or remotely shut down the stolen computer.

SATA Data Cable

Serial ATA cable for attaching devices such as hard-drives and optical drive. This cable transmits data only.

Network Attached Storage (NAS)

Servers that are connected to a network to provide file-level data storage to clients. This specialized computer is sometimes single-purposed, running a stripped-down operating system to perform only the function of file serving. Sometimes the device can offer additional functionality such as media streaming, network services, automated backup functions, website hosting, and many other services.

Pixel

Short for "picture element" it is the fundamental unit of a digital image, typically a tiny square or dot which contains a single point of color of a larger image.

IDE Cable

Similar to SCSI Connectors, but uses 40-pin connectors. There are typically three connectors on the cable. One to connect to the IDE port on the motherboard and two for attachment of IDE drives. Used for older models of disk drives, floppy drives, and hard drives.

Micro-USB

Smallest type of USB, commonly used for mobile phones and tablets.

Thick Client

Standard computers that have their own operating system, a multitude of applications, and local storage. They are stand-alone systems and do not require a network connection to operate. All of the processing is performed locally on the computer.

VGA (Video Graphics Array)

Standard for the video graphics adapter that was introduced in 1987. It supports 16 colors in a 640 × 480 pixel video display. Legacy.

Mirroring RAID

Stores duplicate data on one or more other drives. This provides redundancy so that the failure of a drive does not cause the loss of data. Can be recreated by replacing the drive and restoring the data from the good drive.

Spike

Sudden increase in voltage that lasts for a short period and exceeds 100 percent of the normal voltage on a line. Spikes can be caused by lightning strikes, but can also occur when the electrical system comes back on after a blackout.

SVGA (super video graphics array)

Supports a resolution of 800 × 600. Introduced in 1989, Still supported on some platforms. HD.

Hyper-Threading

The Intel technology that allows each logical processor within the processor package to handle an individual thread in parallel with other threads being handled by other processors within the package.

Response time

The amount in time for a pixel to change properties (i.e., color or brightness)

Dot pitch

The amount of space between pixels, which affects the display quality of images shown on a monitor.

front side bus (FSB)

The bus between the CPU and memory on the motherboard. The bus frequency in documentation is called the system speed, such as 400 MHz. Also called the memory bus, front-side bus, local bus, or host bus.

power-on self-test (POST)

The first job the basic input/output system (BIOS) performs, ensuring that essential peripheral devices are attached and operational. This process consists of a test on the video card and video memory, a BIOS identification process (during which the BIOS version, manufacturer, and data are displayed on the monitor), and a memory test to ensure memory chips are working properly.

Aspect ratio

The horizontal to vertical measurement of the viewing area of a monitor.

Screen size

The measurement in inches from one corner of the screen diagonally across to the opposite corner

USB Type-A

The most common computer port. used to connect a variety of devices, such as printers, scanners, cameras, and more.

unshielded twisted pair (UTP) cable

The most popular cabling method for local networks and is the least expensive and is commonly used on LANs. The cable is made of twisted pairs of wires and is not surrounded by shielding.

Resistance

The opposition that a device or material offers to the flow of direct current.

Multicore Processor

Two or more processors on the same integrated circuit. In some architectures, the cores have separate L2 and L3 cache resources, while in other architectures cache is shared among the different cores for better performance and resource allocation.

GPU Cooling System

Typically come equipped with one or more fans.

Thin Client

Typically low-end network computers that rely on remote servers to perform all data processing. Requires a network connection to a server and usually accesses resources using a web browser. Typically the clients do not have any internal storage and have very little local resources.

UHD (Ultra High Definition)

Ultra High-Definition, Also known as 4K.

GHz

Unit of measurement for a processor's clock speed. 1000 MHz.

Water Cooling System

Used by computers with extremely fast CPUs- metal plate is paced over processor, water pumped over the top to collect the heat, pumped to a radiator to release heat, then recirculated

External SCSI Cable

Used for connecting older external SCSI devices such as scanners and printers. This connector came in 36-pin and 50-pin versions. The pins are arranged in two rows with a plastic bar through the center that holds the contact pins. Squeeze latches or bail locks located on the sides of the connector are used to hold it in place.

eSATA cable

Used to connect external SATA drives.

Complex Instruction Set Computer (CISC)

Uses a broad set of instructions, resulting in fewer steps per operation. Most modern PCs use this type of CPU.

Reduced Instruction Set Computer (RISC)

Uses a relatively small set of instructions; designed to execute these instructions very rapidly. PowerPC and ARM use these.

Native mode

When the image sent to the monitor by the video adapter card matches the native resolution of the monitor.

BIOS

a ROM chip on the motherboard that contains a small program. This program controls the communication between the operating system and the hardware. It also reads the configured settings stored in CMOS to determine how to configure the hardware.

SATA Cable

a cable that connects a hard drive to the motherboard. It has a 7 pin connectors on each end.

Redundant Array of Independent Disks (RAID)

a collection of disk drives used for fault tolerance and improved performance, and is typically found in large network systems

Voltage

a measure of the work associated with moving an electric charge from one point to another

CPU Fan

fan specifically for the CPU to keep it cool. Moves heat away from the metal fins of the heatsink

Parallel Port

female 25-pin port on a computer that can transmit data in parallel, 8 bits at a time, and is usually used with a printer. The names for parallel ports are LPT1 and LPT2.

Brightness

the luminance of a monitor measured in candelas per square meter (cd/m2)