rambus DRAM (RDRAM)

Rambus Dynamic RAM (RDRAM) is a video RAM( VRAM). It was developed by the Rambus company. The special interface design with a modified bus system forms a memory subsystem with the highest transfer rates. The subsystem is composed of the Rambus Channel Master, the Rambus Channel and the Rambus Channel Slave through which communication with the processor or other units takes place.

Rambus technology is a bus technology with a 16-bit bus in which the memory modules are arranged in series. Unused RIMM slots must be populated with empty modules, the CRIMMs. In addition, Rambus technology has a separate control and address bus, efficient protocols, low- voltage signals and clocks very precisely, minimizing propagation time differences( skew) between the clock signal and the data lines.

Rambus technology operates at Double Date Rate( DDR) and clock rates of 400 MHz, resulting in data transfer rates of 1.6 GB/s in conjunction with the 16-bit bus. Since 2 or 4 channels can be used in parallel with Rambus technology, an increase in the data transfer rate to 3.2 GB/s and even to 6.4 GB/s is possible.

The Rambus memory is available as dynamic memory (RDRAM) and as Direct Rambus DRAM( DRDRAM).

The patented and licensed Rambus concept can operate at clock rates of up to 800 MHz, it requires changes in the circuit board design and competes with the open concepts of Synchronous Link DRAM( SLDRAM) and Synchronous DRAM( SDRAM) with DDR technology.