U
UAC — user account control— Microsoft Windows® Vista™ security feature that, when enabled, provides an added layer of security between user accounts and access to operating system settings.
UMA — unified memory allocation — System memory dynamically allocated to video.
UPS — uninterruptible power supply — A backup power source used when the electrical power fails or drops to an unacceptable voltage level. A UPS keeps a computer running for a limited amount of time when there is no electrical power. UPS systems typically provide surge suppression and may also provide voltage regulation. Small UPS systems provide battery power for a few minutes to enable you to shut down your computer.
USB — universal serial bus — A hardware interface for a
UTP — unshielded twisted pair — Describes a type of cable used in most telephone networks and some computer networks. Pairs of unshielded wires are twisted to protect against electromagnetic interference, rather than relying on a metal sheath around each pair of wires to protect against interference.
UXGA — ultra extended graphics array — A video standard for video cards and controllers that supports resolutions up to 1600 x 1200.
V
video controller — The circuitry on a video card or on the system board (in computers with an integrated video controller) that provides the video
video memory — Memory that consists of memory chips dedicated to video functions. Video memory is usually faster than system memory. The amount of video memory installed primarily influences the number of colors that a program can display.
video mode — A mode that describes how text and graphics are displayed on a monitor.
video resolution — See resolution.
Glossary