Manufacturer part number is a unique identifier of a part used in a particular industry. Its purpose is to simplify referencing to that part. A part number unambiguously defines a part within a single manufacturer.
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Computer memory refers to devices that are used to store data or programs on a temporary or permanent basis for use in an electronic digital computer. Volatile memory is computer memory that requires power to maintain the stored information. There are two main types of memory: volatile and non-volatile. Current volatile memory technology is usually either static RAM (SRAM) or dynamic RAM (DRAM).
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DDR2 SDRAM or double-data-rate two synchronous dynamic random access memory is a random access memory technology used for high speed storage of the working data of a computer or other digital electronic device. It is a part of the SDRAM (synchronous dynamic random access memory) family of technologies, which is one of many DRAM (dynamic random access memory) implementations, and is an evolutionary improvement over its predecessor, DDR SDRAM. Its primary benefit is the ability to operate the external data bus twice as fast as DDR SDRAM. This is achieved by improved bus signaling, and by operating the memory cells at half the clock rate (one quarter of the data transfer rate), rather than at the clock rate as in the original DDR. DDR2 memory at the same clock speed as DDR will provide the same bandwidth but markedly higher latency, providing worse performance.
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A rack unit or U (less commonly RU) is a unit of measure used to describe the height of equipment intended for mounting in a rack. One rack unit is 1.75 inches (44.45 mm) high.
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Opteron is AMD's x86 server and workstation processor line, and was the first processor which supported the AMD64 instruction set architecture (known generically as x86-64).
More on “Opteron” at en.wikipedia.org