Dell OptiPlex 755 User's Guide - Page 376

bus - A communication pathway between the components in your computer. bus speed - The speed, given in MHz, that indicates how fast a bus can transfer information. byte - The basic data unit used by your computer. A byte is usually equal to 8 bits. C C - Celsius - A temperature measurement scale where 0° is the freezing point and 100° is the boiling point of water. cache - A special high-speed storage mechanism which can be either a reserved section of main memory or an independent high-speed storage device. The cache enhances the efficiency of many processor operations. L1 cache - Primary cache stored inside the processor. L2 cache - Secondary cache which can either be external to the processor or incorporated into the processor architecture. carnet - An international customs document that facilitates temporary imports into foreign countries. Also known as a merchandise passport. 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 rewritable version of a CD. Data can be written to a CD-RW disc, and 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. CD-RW/DVD drive - A drive, sometimes referred to as a combo drive, that can read CDs and DVDs 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. COA - Certificate of Authenticity - The Windows alpha-numeric code located on a sticker on your computer. 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 processor and memory or between the processor and devices. CRIMM - continuity rambus in-line memory module - A special module that has no memory chips and is used to fill unused RIMM slots. cursor - The marker on a display or screen that shows where the next keyboard, touch pad, or mouse action will occur. It often is a blinking solid line, an underline character, or a small arrow. D DCM - Dell Client Manager. Dell's utility for remote management DDR SDRAM - double-data-rate SDRAM - A type of SDRAM that doubles the data burst cycle, improving system performance. DDR2 SDRAM - double-data-rate 2 SDRAM - A type of DDR SDRAM that uses a 4-bit prefetch and other architectural changes to boost memory speed to over 400 MHz. device - Hardware such as a disk drive, printer, or keyboard that is installed in or connected to your computer. device driver - See driver. DIMM - dual in-line memory module - A circuit board with memory chips that connects to a memory module on the system board. DIN connector - A round, six-pin connector that conforms to DIN (Deutsche Industrie-Norm) standards; it is typically used to connect PS/2 keyboard or mouse cable connectors. 376 Glossary