Dell OptiPlex GX260 User Guide - Page 212

L2 cache - Also called secondary cache; sometimes refers to cache memory external to the microprocessor, although more recent microprocessors incorporate the L2 cache in their architecture. CD - compact disc - An optical form of storage media, typically used for audio and application programs. CD drive - A drive that uses optical technology to read data from CDs. CD player - The software used to play music CDs. The CD player displays a window with buttons you use to play a CD. CD-R - CD recordable - A recordable version of a CD. Data can be recorded only once onto a CD-R. Once recorded, the data cannot be erased or written over. CD-RW - CD rewritable - A rewriteable version of a CD. Data can be written to a CD-RW, then erased and written over (rewritten). CD-RW drive - A drive that can read CDs and write to CD-RW (rewritable CDs) and CD-R (recordable CDs) discs. You can write to CD-RW discs multiple times, but you can write to CD-R discs only once. Clock speed - The speed, given in MHz, that indicates how fast computer components that are connected to the system bus operate. Components that are synchronized with the clock speed can run faster or slower, but their speed is determined by multiplying or dividing a factor by the clock speed. cm - centimeter - A metric unit of measure equal to 0.39 inch. COA - Certificate of Authenticity - The Windows alpha-numeric code located on a sticker on your computer. You may need the COA to complete the operating system setup or reinstallation. Also referred to as the Product Key or Product ID. Control panel - A Windows utility that allows you to modify operating system and hardware settings, such as display settings. Controller - A chip that controls the transfer of data between the microprocessor and memory or between the microprocessor and devices. CRIMM - continuity rambus in-line memory module- A special module without any memory chips that is used to fill unused RIMM slots. Cursor - The marker on a display or screen that shows where the next keyboard or mouse action will occur. It often is a blinking solid line, an underline character, or a small arrow. D DDR SDRAM - double-data-rate SDRAM - A type of SDRAM that doubles the data burst cycle, improving system performance. Device - Hardware such as a disk drive, printer, or keyboard that is installed in or connected to your computer. Device driver - See driver. DIN connector - A round, six-pin connector that conforms to DIN (Deutsche Industrinorm) standards; it is typically used to connect PS/2 keyboard or mouse cable connectors. Disk striping - A technique for spreading data over multiple disk drives. Disk striping can speed up operations that retrieve data from disk storage. Systems that use disk striping generally allow the user to select the data unit size or stripe width. DMA - direct memory access - A channel that allows certain types of data transfer between RAM and a device to bypass the microprocessor. DMTF - Distributed Management Task Force - A consortium of hardware and software companies who develop management standards for distributed desktop, network, enterprise and Internet environments. DRAM - dynamic random-access memory - Memory that stores information in integrated circuits containing capacitors. Driver - Software that allows the operating system to control a device such as a printer. Many devices do not work properly if the correct driver is not installed in the computer. Dual display mode - A display setting that allows you to use a second monitor as an extension of your display. Also referred to as extended display mode. DVD - digital versatile disc - A disc usually used to store movies. DVDs are double-sided, whereas CDs are single-sided.