GDDR4 can surpass XDR performance in certain scenarios, Samsung says

Samsung yesterday surprised with an announcement that it has begun sampling of GDDR4 memory, which may become the next-generation memory technology for graphics chips. Today, the company told TG Daily that GDDR4 in fact will be fast enough to reach the speed of Rambus' XDR memory technology. In some cases, GDDR4 will be able to even outpace XDR, Mueez Deen, marketing director for graphics, mobile and consumer DRAM, said.

Such a scenario could be graphics card with a 256-bit bus. "GDDR4 will offer a higher performance on such a card than 4-channel XDR," Deen said. He added that GDDR4's performance climbs rapidly, if hardware designers are willing to spend the necessary pin count. On lower pin-counts, XDR has an advantage: "XDR provides a much higher bandwidth per pin," he said.

Samsung confirmed in May of this year that it will be shipping XDR memory to Sony for the Playstation 3 game console. While the current market situation is reminiscent of the battle between Rambus DRAM and the victorious DDR DRAM, Deen said that he believes there will be a place for XDR in the market beyond the Playstation 3. In the end, it will be up to graphic chip developers to decide which memory technology will be become the next mass market graphics memory.

While Deen said that the production cost of XDR and GDDR4 may be comparable, he mentioned that GDDR4 "is an evolutionary step over GDDR3" and therefore developers may be more comfortable working with this technology. A current per-pin performance advantage will not be enough for XDR to succeed, Deen believes: "The bandwidth of XDR needs to increase," he said.