Dell GX240 User's Guide - Page 291

PXE Pre-boot eXecution Environment. A standard of WfM that allows networked computers that do not have an OS to be configured and started remotely. PXE benefits include: • The client computer does not necessarily need its own OS or even a hard drive. • The client computer can be remotely shut down and restarted. • Since PXE is an industry standard, new computers can easily be added to the network. RAID Redundant Array of Independent Disks. A system of two or more drives working together for performance and fault tolerance. RAID drives are typically used on servers and high-end PCs. There are a number of different RAID levels. The three most common are 0, 3, and 5: • Level 0: Provides data striping but no redundancy. This improves performance but does not provide fault tolerance. • Level 3: Same as Level 0, but also reserves one dedicated drive for error correction data, providing good performance and some level of fault tolerance. • Level 5: Provides data striping at the byte level and also stripe error correction information. This results in excellent performance and good fault tolerance. RAM Random-access memory. The primary temporary storage area for program instructions and data. RAM is stored in chips on small circuit boards called SIMMs, DIMMs, or RIMMs, that attach to the system board. RAM, unlike ROM, is volatile, which means that, when you turn off your computer, any information stored in RAM is lost. Rambus Rambus is a memory technology that is designed to work with existing system board standards as an alternative to DRAM. See also RIMM, RDRAM, and DRDRAM. RDRAM Rambus dynamic random-access memory (DRAM). A memory subsystem that can optimally transfer up to 1.6 billion bytes of data per second. The subsystem consists of RAM, the RAM controller, and the bus connecting RAM to the microprocessor and other devices in the computer. See also DRDRAM. 39