| eyeofcore said: DDR3 that does what it is suppose to do and eSRAM as VRAM that is cheaper and faster than GDDR5, but harder to work with and that is reason why games on Xbox One has couple of multi plats that are 720p and not 900p or 1080p. Xbox One has 32MB of eSRAM that is ultra fast and it only needs 16MB to achieve 1080p in single pass and rest can be used for AA's and other things. |
I can assure you that esram is a lot, and I mean _A LOT_ more expensive than gddr5 ram. That really is a no-brainer since the 32Mbyte take up about 70-80mm^2 die space, that is more than half of a cell processor, so you are looking at $10 for 32Mbyte of esram. 32MByte of gddr5 ram is 1/16 of a chip, so you are looking at <$1 for 32MByte. Secondly, the esram has absolutely nothing to do with vram, it is software managed cache. Thirdly, the esram is not ultra-fast, for all we really know it is a 4*256bit bus connected to a 853MHz quadruple of memory controllers that give you a 109GB/s bandwidth. There is voodoo-math by pr people ("We just discovered that can read and write at the same time") which suddenly doubles the numbers, but until someone really explains that voodoo bit, we can stick with a safe 109GB/s value. Fourthly, I don't get what you are trying to say in your last sentence. A 1080p g-buffer would eat 24Mbyte of your esram alone (hence why Ryse is only 900p, there wasn't enough esram left for the rest at 1080p).
