Dell Precision 420 User Manual page 55

without starting any TSR programs.
U
UL
Underwriters Laboratories
UMB
upper memory blocks.
upper memory area
The 384 KB of RAM located between 640 KB and 1 MB. If the computer has an Intel386 or higher microprocessor, a utility called a memory
manager can create UMBs in the upper memory area, in which you can load device drivers and memory-resident programs.
UPS
uninterruptible power supply. A battery-powered unit that automatically supplies power to your computer in the event of an electrical failure.
USB
Universal Serial Bus. A USB connector provides a single connection point for multiple USB-compliant devices, such as mice, keyboards, printers,
and computer speakers. USB devices can also be connected and disconnected while the system is running.
utility
A program used to manage system resources—memory, disk drives, or printers, for example.
UTP
unshielded twisted pair
V
V
volt(s)
VAC
volt(s) alternating current
VCCI
Voluntary Control Council for Interference
VCR
videocassette recorder
VDC
volt(s) direct current
VESA
Video Electronics Standards Association
VGA
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 memory installed
for the video adapter.
VGA feature connector
On some systems with an integrated VGA video adapter, a VGA feature connector allows you to add an enhancement adapter, such as a video