4R256CEE6C

The Direct Rambus RIMM module is a general-purpose high-performance memory module subsystem suitable for use in a broad range of applications including computer memory, personal computers, workstations, and other applications where high bandwidth and low latency are required.

MC-4R256CEE6B, 4R256CEE6C modules consists of sixteen 128M Direct Rambus DRAM (Direct RDRAM™) devices(µPD488448).  These are extremely high-speed CMOS DRAMs organized as 8M words by 16 bits.  The use of Rambus Signaling Level (RSL) technology permits 600MHz, 711MHz or 800MHz transfer rates while using conventional system and board design technologies.

Direct RDRAM devices are capable of sustained data transfers at 1.25 ns per two bytes (10 ns per sixteen bytes). The architecture of the Direct RDRAM enables the highest sustained bandwidth for multiple, simultaneous, randomly addressed memory transactions.  The separate control and data buses with independent row and column control yield over 95 % bus efficiency.  The Direct RDRAM's 32 banks support up to four simultaneous transactions per device.