One of the most important things related to the arrival of the next generation consoles such as PlayStation 4 and Xbox One is the related RAM that will be arriving with them. While Microsoft is working with an 8GB DDR3 RAM for the Xbox One, the developing team states that it’s much easier to work with the on board ESRAM.
Recently in an interview with Eurogamer, Nick Baker, of the Xbox One’s architecture team, stated that with the introduction of ESRAM, there will be a balance of bandwidth and power that will be generated via the new console. He also added that although it’s quite uncomfortable to work with the GDDR5, the application of ESRAM makes the job easier.
On asked if it’s a fair assumption that Microsoft wanted to tap into the power of the ESRAM and that’s why it ruled out GDDR5 in favor of ESRAM in combination with DDR3, Baker stated:
“Yeah, I think that's right. In terms of getting the best possible combination of performance, memory size, power, the GDDR5 takes you into a little bit of an uncomfortable place. Having ESRAM costs very little power and has the opportunity to give you very high bandwidth.”
“You can reduce the bandwidth on external memory - that saves a lot of power consumption as well and the commodity memory is cheaper as well so you can afford more. That's really a driving force behind that. You're right, if you want a high memory capacity, relatively low power and a lot of bandwidth there are not too many ways of solving that,” he said.
It was also pointed out that the peak bandwidth was a lot smaller when the specs of the device were revealed on the leaked whitepapers, but was later doubled with production silicon. To justify this, Baker added:
“When we started, we wrote a spec. Before we really went into any implementation details, we had to give developers something to plan around before we had the silicon, before we even had it running in simulation before tape-out, and said that the minimum bandwidth we want from the ESRAM is 102GB/s. That became 109GB/s [with the GPU speed increase]. In the end, once you get into implementing this, the logic turned out that you could go much higher.”
Microsoft’s Xbox One is currently set for a November 2013 release.