Dell™ PowerEdge™ 1750 Systems User's Guide
The following list defines or identifies technical terms, abbreviations, and acronyms used in your system documents.
Abbreviation for alternating current.
Abbreviation for Advanced Configuration and Power Interface.
An expansion card that plugs into an expansion-card connector on the computer's system board. An adapter card adds some specialized function to the system by providing an interface between the expansion bus and a peripheral device. Examples of adapter cards include network cards, sound cards, and SCSI adapters.
The temperature of the area or room where the system is located. Also known as room temperature.
Abbreviation for American National Standards Institute.
Software, such as a spreadsheet or word processor, designed to help you perform a specific task or series of tasks. Application programs run from the operating system.
An individual code assigned to a system, usually by a system administrator, for security or tracking purposes.
A copy of a program or data file. As a precaution, you should back up your system's hard drive on a regular basis. Before making a change to the configuration of your system, you should back up important start-up files from your operating system.
The backup battery maintains system configuration, date, and time information in a special section of memory when the system is turned off.
A diagnostic message in the form of a pattern of beeps from your system's speaker. For example, one beep, followed by a second beep, and then a burst of three beeps is beep code 1-1-3.
Acronym for basic input/output system. Your system's BIOS contains programs stored on a flash memory chip. The BIOS controls the following:
The smallest unit of information interpreted by your system.
When you start your system, it clears all memory, initializes devices, and loads the operating system. Unless the operating system fails to respond, you can reboot (also called warm boot) your system by pressing <Ctrl><Alt><Del>; otherwise, you must perform a cold boot by pressing the reset button or by turning the system off and then back on.
You can start your system from a bootable diskette. To make a bootable diskette, insert a diskette in the diskette drive, type sys a: at the command line prompt, and press <Enter>. Use this bootable diskette if your system will not boot from the hard drive.
Abbreviation for bits per second.
Abbreviation for British thermal unit.
An information pathway between the components of a system. Your system contains an expansion bus that allows the microprocessor to communicate with controllers for all the various peripheral devices connected to the system. Your system also contains an address bus and a data bus for communications between the microprocessor and RAM.
Eight contiguous bits of information, the basic data unit used by your system.
A fast storage area that keeps a copy of data or instructions for quicker data retrieval. For example, your system's BIOS may cache ROM code in faster RAM. Or, a disk-cache utility may reserve RAM in which to store frequently accessed information from your system's disk drives; when a program makes a request to a disk drive for data that is in the cache, the disk-cache utility can retrieve the data from RAM faster than from the disk drive.
Abbreviation for compact disc. CD drives use optical technology to read data from CDs. CDs are read-only storage devices; you cannot write new data to a CD with standard CD drives.
The device names for the first through fourth serial ports are COM1, COM2, COM3, and COM4. The default interrupt for COM1 and COM3 is IRQ4, and the default interrupt for COM2 and COM4 is IRQ3. Therefore, you must be careful when configuring software that runs a serial device so that you don't create an interrupt conflict.
A chip that controls the transfer of data between the microprocessor and memory or between the micro-processor and a peripheral device such as a disk drive or the keyboard.
The part of the system that contains indicators and controls, such as the power switch, hard drive access indicator, and power indicator.
Abbreviation for central processing unit. See microprocessor.
Abbreviation for direct current.
Abbreviation for double-data rate.
A program that allows the operating system or some other program to interface correctly with a peripheral device, such as a printer. Some device drivers—such as network drivers—must be loaded from the config.sys file (with a device= statement) or as memory-resident programs (usually, from the autoexec.bat file). Others—such as video drivers—must load when you start the program for which they were designed.
Acronym for Dynamic Host Configuration Protocol.
A comprehensive set of tests for your system. See your Installation and Troubleshooting Guide for more information about using diagnostics.
Acronym for dual in-line memory module. A small circuit board containing DRAM chips that connects to the system board.
Acronym for Deutsche Industrie Norm.
Directories help keep related files organized on a disk in a hierarchical, "inverted tree" structure. Each disk has a "root" directory; for example, a c:\> prompt normally indicates that you are at the root directory of hard drive C. Additional directories that branch off the root directory are called subdirectories. Subdirectories may contain additional directories branching off them.
Abbreviation for direct memory access. A DMA channel allows certain types of data transfer between RAM and a device to bypass the microprocessor.
Abbreviation for Domain Name System.
Abbreviation for dynamic random-access memory. A system's RAM is usually made up entirely of DRAM chips. Because DRAM chips cannot store an electrical charge indefinitely, your system continually refreshes each DRAM microprocessor in the system.
Abbreviation for digital versatile disk.
Abbreviation for error checking and correction.
Acronym for electrically erasable programmable read-only memory.
Abbreviation for Electromagnetic Compatibility.
Abbreviation for electromagnetic interference.
Abbreviation for embedded remote access option. ERA/O allows you to perform remote, or "out-of-band," server management on your network server using an optional remote access controller (RAC) card.
Abbreviation for electrostatic discharge.
Your system contains an expansion bus that allows the microprocessor to communicate with controllers for peripheral devices, such as a network card.
A connector on the system board or riser board for plugging in an expansion card.
Acronym for file allocation table. The file system structure used by MS-DOS® to organize and keep track of file storage. The Windows NT® operating systems can optionally use a FAT file system structure.
Abbreviation for Federal Communications Commission.
A type of EEPROM chip that can be reprogrammed from a utility on diskette while still installed in a system; most EEPROM chips can only be rewritten with special programming equipment.
To prepare a hard drive or diskette for storing files. An unconditional format deletes all data stored on the disk.
Abbreviation for front side bus. The FSB is the data path and physical interface between the microprocessor and the main memory (RAM).
Abbreviation for file transfer protocol.
A type of data redundancy that uses a set of physical drives to store data and a single, additional drive to store parity data. Data is protected from the loss of a single drive. Guarding is sometimes preferred over mirroring because it is more cost-effective in systems with a very high storage capacity. However, guarded configurations are significantly slower for applications that frequently write to the array because each attempt to the array requires multiple read and write commands to maintain the parity information. If this is a problem, mirroring is a better choice. See also mirroring, RAID 4, and RAID 5.
Abbreviation for gigabyte(s). A gigabyte equals 1,024 megabytes or 1,073,741,824 bytes.
Abbreviation for gigabit(s). A gigabit equals one billion bits.
A video mode that can be defined as x horizontal by y vertical pixels by z colors.
Abbreviation for hexadecimal. A base-16 numbering system, often used in programming to identify addresses in the system's RAM and I/O memory addresses for devices. The sequence of decimal numbers from 0 through 16, for example, is expressed in hexadecimal notation as 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F, 10. In text, hexadecimal numbers are often followed by h.
A system or device that functions without having a keyboard, mouse, or monitor attached. Normally, headless systems are managed over an internet or intranet network using an internet browser. Some systems provide for attaching a keyboard, mouse, and monitor for specific management or service needs, others do not.
A host adapter implements communication between the system's bus and the controller for a peripheral device. (Hard drive controller subsystems include integrated host adapter circuitry.) To add a SCSI expansion bus to your system, you must install or connect the appropriate host adapter.
Abbreviation for integrated drive electronics
Abbreviation for input/output. A keyboard is an input device, and a printer is an output device. In general, I/O activity can be differentiated from computational activity. For example, when a program sends a document to the printer, it is engaging in output activity; when the program sorts a list of terms, it is engaging in computational activity.
Abbreviation for identification.
A technique for increasing video resolution by only up-dating alternate horizontal lines on the screen. Because interlacing can result in noticeable screen flicker, most users prefer noninterlaced video adapter resolutions.
Abbreviation for Internet Protocol.
Abbreviation for Internetwork Packet EXchange.
Abbreviation for interrupt request. A signal that data is about to be sent to or received by a peripheral device travels by an IRQ line to the microprocessor. Each peripheral connection must be assigned an IRQ number. For example, the first serial port in your system (COM1) is assigned to IRQ4 by default. Two devices can share the same IRQ assignment, but you cannot operate both devices simultaneously.
Abbreviation for information technology equipment.
Jumpers are small blocks on a circuit board with two or more pins emerging from them. Plastic plugs containing a wire fit down over the pins. The wire connects the pins and creates a circuit. Jumpers provide a simple and reversible method of changing the circuitry in a printed circuit board.
Abbreviation for kilo-, indicating 1,000.
Abbreviation for kilobyte(s), 1,024 bytes.
Abbreviation for kilobyte(s) per second.
Abbreviation for kilobit(s), 1,024 bits.
Abbreviation for kilobit(s) per second.
A command requiring you to press multiple keys at the same time. For example, you can reboot your system by pressing the <Ctrl><Alt><Del> key combination.
Abbreviation for kilogram(s), 1,000 grams.
Abbreviation for kilohertz, 1,000 hertz.
Acronym for local area network. A LAN system is usually confined to the same building or a few nearby buildings, with all equipment linked by wiring dedicated specifically to the LAN.
Abbreviation for light-emitting diode. An electronic device that lights up when a current is passed through it.
A version of UNIX® that runs on a variety of hardware systems. Linux is open source software, which is freely available; however, the full distribution of Linux along with technical support and training are available for a fee from vendors such as Red Hat Software (www.redhat.com).
On a system with local-bus expansion capability, certain peripheral devices (such as the video adapter circuitry) can be designed to run much faster than they would with a traditional expansion bus. Some local-bus designs allow peripherals to run at the same speed and with the same width data path as the system's microprocessor.
Abbreviation for milliampere(s).
Abbreviation for Media Access Control.
Abbreviation for milliampere-hour(s).
Abbreviation for megabyte(s). The term megabyte means 1,048,576 bytes; however, when referring to hard drive storage, the term is often rounded to mean 1,000,000 bytes.
Abbreviation for megabytes per second.
Abbreviation for megabits per second.
Abbreviation for master boot record.
A specific location, usually expressed as a hexadecimal number, in the system's RAM.
A small circuit board containing DRAM chips that connects to the system board.
The primary computational chip inside the system that controls the interpretation and execution of arithmetic and logic functions. Software written for one microprocessor must usually be revised to run on another microprocessor. CPU is a synonym for microprocessor.
A type of data redundancy that uses a set of physical drives to store data and one or more sets of additional drives to store duplicate copies of the data. Mirroring is the preferred data redundancy technique in lower-capacity systems and in systems where performance is extremely important. See also guarding, RAID 1, and RAID 10.
Abbreviation for millimeter(s).
Acronym for Motion Picture Experts Group. MPEG is a digital video file format.
Abbreviation for millisecond(s).
Abbreviation for Microsoft Disk Operating System.
Abbreviation for Network Attached Storage. Network-attached storage (NAS) is one of the concepts used for implementing shared storage on a network. The network communication uses Common Internet File System (CIFS) for Microsoft Windows environments, Network File System (NFS) for UNIX environments, FTP, http, and other networking protocols.
Abbreviation for Network Driver Interface Specification.
Acronym for network interface controller.
Abbreviation for nonmaskable interrupt. A device sends an NMI to signal the microprocessor about hardware errors, such as a parity error.
A technique for decreasing screen flicker by sequentially refreshing each horizontal line on the screen.
Abbreviation for nanosecond(s), one billionth of a second.
Abbreviation for the NT File System option in the Windows NT operating system.
Abbreviation for nonvolatile random-access memory. Memory that does not lose its contents when you turn off your system. NVRAM is used for maintaining the date, time, and system configuration information.
You can divide a hard drive into multiple physical sections called partitions with the fdisk command. Each partition can contain multiple logical drives.
After partitioning the hard drive, you must format each logical drive with the format command.
Redundant information that is associated with a block of information.
RAID 5 volumes, for example, stripe data and parity intermittently across a set of hard drives. Within each stripe, the data on one hard drive is parity data and the data on the other hard drives is normal data. RAID 5 volumes therefore require at least three hard drives to allow for this extra parity information. See RAID 0 and RAID 5.
Abbreviation for Peripheral Component Interconnect. PCI is a standard for local-bus implementation developed by Intel Corporation.
Abbreviation for power distribution unit. A PDU is a power source with multiple power outlets that provides electrical power to servers and storage systems in a rack.
An internal or external device—such as a printer, a disk drive, or a keyboard—connected to a system.
Abbreviation for pin grid array, a type of microprocessor socket that allows you to remove the microprocessor chip.
A single point on a video display. Pixels are arranged in rows and columns to create an image. A video resolution, such as 640 x 480, is expressed as the number of pixels across by the number of pixels up and down.
Acronym for power-on self-test. Before the operating system loads when you turn on your system, the POST tests various system components such as RAM, the disk drives, and the keyboard.
The set of diskettes from which you can perform a complete installation of an operating system or application program. When you reconfigure a program, you often need its program diskette set.
An operating mode supported by 80286 or higher microprocessors, protected mode allows operating systems to implement:
The Windows NT and UNIX 32-bit operating systems run in protected mode. MS-DOS cannot run in protected mode; however, some programs that you can start from MS-DOS, such as the Windows operating system, are able to put the system into protected mode.
Abbreviation for Personal System/2.
Acronym for Preboot Execution Environment.
Acronym for remote access controller.
Acronym for redundant array of independent disks. An array of multiple independent hard drives that, in varying levels, provide high performance and fault tolerance.
The following RAID levels provide various mixes of performance, reliability, and cost: Level 0 (striping), Level 1 (mirroring), Level 5 (striping with parity), Level 10 (striping with mirroring) and Level 50 (linked Level 5 arrays).
RAID 0 is commonly called striping. This was not originally defined as a RAID level but has since come into popular use. In this array configuration, data is written sequentially across the available disks and no redundancy is provided. RAID 0 configurations provide very high performance but relatively low reliability. RAID 0 is the best choice when controller cards are duplexed. See striping.
RAID 1 is commonly called mirroring. RAID 1 also uses striping, so RAID 1 may be regarded as the mirroring of RAID 0 configurations. RAID 1 is the best choice in high-availability applications that require high performance or relatively low data capacity. See mirroring, RAID 10, and striping.
RAID 3 is commonly called guarding. It uses data striping, like RAID 0, but adds a single, dedicated parity drive for redundancy and block-level parallel access. The parity data stored on this drive can be used to recover data lost from a single failed drive, and the generation of the parity data frequently requires reading data from multiple physical drives. RAID 3 is generally used in situations that require large sequential I/Os and a high data-transfer rate, such as video streaming. See guarding and striping.
RAID 4 is commonly called guarding. It uses a single, dedicated parity drive, like RAID 3, but requires reading and writing large blocks of data to one physical drive at a time. See guarding and striping.
RAID 5 is commonly called guarding. RAID 5 is identical to RAID 4, except that the parity data is distributed evenly across all physical drives instead of a parity drive. In configurations using a large number of physical drives in which a large number of simultaneous small write operations are being performed, RAID 5 offers potentially higher performance than RAID 4. RAID 4 and RAID 5 configurations are appropriate in high-availability applications where performance is less critical or where high data capacity is required. See guarding.
RAID 10 is commonly called RAID 1+0. RAID 10 is a multilevel array that combines mirrored drives (RAID 1) with data striping (RAID 0). In a RAID 10 configuration, data is mirrored on two drives and then striped across two or more sets of mirrored drives. RAID 10 offers the data transfer advantages of striped arrays and the accessibility features of mirrored arrays. System performance during a drive rebuild is also better than parity-based arrays, since data does not need to be regenerated from parity information, but simply copied from a surviving drive.
Two or more linked RAID 5 arrays. For example, a RAID 5 array that is implemented with three drives and then continues on with three more array drives would be a RAID 50 array. RAID 50 provides data redundancy through parity. See parity.
Acronym for random-access memory. The system's primary temporary storage area for program instructions and data. Each location in RAM is identified by a number called a memory address. Any information stored in RAM is lost when you turn off your system.
Abbreviation for Remote Access Service. This service allows users running the Windows operating system to remotely access a network from their system using a modem.
A read-only file is one that you are prohibited from editing or deleting. A file can have read-only status if:
A text file included with a software package or hardware product that contains information supplementing or updating the documentation for the software or hardware. Typically, readme files provide installation information, describe new product enhancements or corrections that have not yet been documented, and list known problems or other things you need to be aware of as you use the software or hardware.
Acronym for read-only memory. Your system contains some programs essential to its operation in ROM code. Unlike RAM, a ROM chip retains its contents even after you turn off your system. Examples of code in ROM include the program that initiates your system's boot routine and the POST.
Acronym for RAID on Motherboard.
Abbreviation for revolutions per minute.
Abbreviation for real-time clock. Battery-powered clock circuitry inside the system that keeps the date and time after you turn off the system.
Acronym for small computer system interface. An I/O bus interface with faster data transmission rates than standard ports. You can connect up to seven devices (15 for some newer SCSI types) to one SCSI interface.
Abbreviation for SCSI device management system.
Acronym for synchronous dynamic random-access memory.
An I/O port used most often to connect a modem to your system. You can usually identify a serial port on your system by its 9-pin connector.
A bar code label on the system that identifies it when you call customer or technical support.
Acronym for single in-line memory module. A small circuit board containing DRAM chips that connects to the system board.
Acronym for Self-Monitoring Analysis and Reporting Technology. A technology that allows hard drives to report errors and failures to the system BIOS, which then displays an error message on the screen. To take advantage of this technology, you must have a SMART-compliant hard drive and the proper support in the system BIOS.
Abbreviation for Simple Network Management Protocol. SNMP is an industry-standard interface that allows a network manager to remotely monitor and manage workstations.
Abbreviation for static random-access memory. Because SRAM chips do not require continual refreshing, they are substantially faster than DRAM chips.
Disk striping writes data across 3 or more array disks. Each "stripe" spans 3 or more array disks but only consumes a portion of each disk. The amount of space consumed by a stripe is the same on each array disk included in the stripe. A virtual disk may use several stripes on the same set of array disks.
Abbreviation for super video graphics array. VGA and SVGA are video standards for video adapters with greater resolution and color display capabilities than previous standards.
To display a program at a specific resolution, you must install the appropriate video drivers and your monitor must support the resolution. Similarly, the number of colors that a program can display depends on the capabilities of the monitor, the video driver, and the amount of video memory installed in the system.
As the main circuit board, the system board usually contains most of your system's integral components, such as the following:
Frequently used synonyms for system board are motherboard and logic board.
Data stored in memory that tells a system what hardware is installed and how the system should be configured for operation.
System diskette is a synonym for bootable diskette.
System memory is a synonym for RAM.
A BIOS-based program that allows you to configure your system's hardware and customize the system's operation by setting such features as password protection and energy management. Some options in the System Setup program require that you reboot the system (or the system may reboot automatically) in order to make a hardware configuration change. Because the System Setup program is stored in NVRAM, any settings remain in effect until you change them again.
A start-up file for the Windows operating system. When you start Windows, it consults the system.ini file to determine a variety of options for the Windows operating environment. Among other things, the system.ini file records which video, mouse, and keyboard drivers are installed for Windows.
Running the Control Panel or Windows Setup program may change options in the system.ini file. On other occasions, you may need to change or add options to the system.ini file manually with a text editor, such as Notepad.
Some devices (such as the last device at each end of a SCSI cable) must be terminated to prevent reflections and spurious signals in the cable. When such devices are connected in a series, you may need to enable or disable the termination on these devices by changing jumper or switch settings on the devices or by changing settings in the configuration software for the devices.
A video mode that can be defined as x columns by y rows of characters.
Abbreviation for Underwriters Laboratories.
Abbreviation for upper memory blocks.
Abbreviation for UNiversal Internet eXchange. UNIX, precursor to Linux, is an operating system written in the C programming language. Known for its portability and flexibility, UNIX has become a leading operating system for computer workstations.
Abbreviation for uninterruptible power supply. A battery-powered unit that automatically supplies power to your system in the event of an electrical failure.
Abbreviation for Universal Serial Bus. A USB connector provides a single connection point for multiple USB-compliant devices, such as mice, keyboards, printers, and system speakers. USB devices can also be connected and disconnected while the system is running.
A program used to manage system resources—memory, disk drives, or printers, for example.
Abbreviation for unshielded twisted pair.
Abbreviation for volt(s) alternating current.
Abbreviation for Voluntary Control Council for Interference.
Abbreviation for volt(s) direct current.
Abbreviation for video graphics array. VGA and SVGA are video standards for video adapters with greater resolution and color display capabilities than previous standards.
To display a program at a specific resolution, you must install the appropriate video drivers and your monitor must support the resolution. Similarly, the number of colors that a program can display depends on the capabilities of the monitor, the video driver, and the amount of video memory installed for the video adapter.
The logical circuitry that provides—in combination with the monitor—your system's video capabilities. A video adapter may support more or fewer features than a specific monitor offers. Typically, a video adapter comes with video drivers for displaying popular application programs and operating systems in a variety of video modes.
On some systems, a video adapter is integrated into the system board. Also available are many video adapter cards that plug into an expansion-card connector.
Video adapters often include memory separate from RAM on the system board. The amount of video memory, along with the adapter's video drivers, may affect the number of colors that can be simultaneously displayed. Video adapters can also include their own coprocessor for faster graphics rendering.
A program that allows graphics-mode application programs and operating systems to display at a chosen resolution with the desired number of colors. A software package may include some "generic" video drivers. Any additional video drivers may need to match the video adapter installed in the system.
Most VGA and SVGA video adapters include memory chips in addition to your system's RAM. The amount of video memory installed primarily influences the number of colors that a program can display (with the appropriate video drivers and monitor capabilities).
Video adapters normally support multiple text and graphics display modes. Character-based software displays in text modes that can be defined as x columns by y rows of characters. Graphics-based software displays in graphics modes that can be defined as x horizontal by y vertical pixels by z colors.
Video resolution is expressed as the number of pixels across by the number of pixels up and down. To display a program at a specific graphics resolution, you must install the appropriate video drivers and your monitor must support the resolution.
Abbreviation for video random-access memory. Some video adapters use VRAM chips (or a combination of VRAM and DRAM) to improve video performance. VRAM is dual-ported, allowing the video adapter to update the screen and receive new image data at the same time.
Abbreviation for watt-hour(s).
A start-up file for the Windows operating system. When you start Windows, it consults the win.ini file to determine a variety of options for the Windows operating environment. Among other things, the win.ini file records what printer(s) and fonts are installed for Windows. The win.ini file also usually includes sections that contain optional settings for Windows application programs that are installed on the hard drive.
Running the Control Panel or Windows Setup program may change options in the win.ini file. On other occasions, you may need to change or add options to the win.ini file manually with a text editor such as Notepad.
A set of Microsoft software technologies that enable software integration through the use of XML Web services. XML Web services are small reusable applications written in XML that allow data to be communicated between otherwise unconnected sources.
An integrated and complete Microsoft Windows operating system that does not require MS-DOS and that provides advanced operating system performance, improved ease of use, enhanced workgroup functionality, and simplified file management and browsing.