Rambus Proposes Micro-Threading to Boost GDDR Performance

Rambus’ New Tech Increases Memory Performance by Up to 4 Times

by Anton Shilov
04/04/2005 | 03:16 PM

Rambus unveiled Monday a technology which is said to significantly increases memory subsystem efficiency, resulting in up to four times greater performance when compared to a traditional DRAM in applications such as 3D graphics, advanced video imaging, and network routing and switching. The tech relies on partitioning of each memory device and ability to save transaction cycles.

 

Micro-threading increases memory system efficiency by enabling DRAMs to provide more usable data bandwidth to requesting memory controllers. A single core operation of a typical mainstream DRAM provides a larger amount of data than needed by many applications. As a result, large amounts of memory bandwidth are used to deliver a small amount of relevant data. Micro-threading enables the DRAM to provide several smaller relevant pieces of data in place of a single larger piece of data, resulting in higher memory bandwidth efficiency while minimizing power consumption.

With the application of micro-threading to a DRAM core, separate addresses are provided to different DRAM core partitions, enabling the requesting controller to generate multiple micro-RAS and micro-CAS operations in the same time it would take to generate a single RAS or CAS command to a standard DRAM. Simultaneously accessible banks allow for concurrent retrieval of data, which are then bundled into a single transmission.

Micro-threading may be applied to existing DRAM cores with relatively low incremental cost, Rambus said. To benefit from the performance increase, DRAM controllers interfacing with micro-threaded DRAMs need to be optimized for the new technology. This patent pending micro-threading technology is available for licensing today.

A Rambus analysis showed that a standard GDDR SDRAM being used in a 3D application can deliver between 50 and 125 million triangles per second, the company said. If the same GDDR SDRAM were to be enhanced with micro-threading, the rate of delivered triangles would increase to between 100 and 500 million triangles per second. By enabling higher triangle rendering rates, micro-threading, as it is applied to a DRAM core, benefits the end user experience by providing richer visuals, Rambus believes.