Dell PowerVault 775N (Rackmount NAS Appliance) User Manual
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component.
h
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.
host adapter
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.
Hz
Abbreviation for hertz.
IDE
Abbreviation for integrated drive electronics
I/O
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.
ID
Abbreviation for identification.
interlacing
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.
internal microprocessor cache
An instruction and data cache built in to the microprocessor. The Intel Pentium microprocessor includes a 16-KB internal
cache, which is set up as an 8-KB read-only instruction cache and an 8-KB read/write data cache.
IRQ
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.
ISA
Acronym for Industry-Standard Architecture. A 16-bit expansion bus design. The expansion-card connectors in an ISA system
are also compatible with 8-bit ISA expansion cards.
ITE