Do you guys know how to calculate real latency for memory ? it appears there is some misunderstanding here.
Latency is not just defined by the CAS number, it's (CL/data rate) x 2000 or (CL/base clock) x 1000.
Xone memory chips are 2133 Mhz CAS 14, that's probably really cheap DDR3, but that was the point to choose cheap memory from the start and get a huge amount of it (8 GB), so you can't blame them for this.
It's in the micron pdf related to the chips that have been identified on the inside Xone pictures :
So their real latency is(14/2133)x2000= 13.09 ns (exactly what's described in the pdf)
Now let's take a look at the GDDR5 produced by Samsung for the PS4, it's there :
http://www.samsung.com/global/business/semiconductor/product/graphic-dram/resource
Also the Elpida equivalent in 2gb modules :
http://www.elpida.com/pdfs/E1864E10.pdf
Worst case scenario on both is a CL 20 (it's in the pdf) : 20/5500x2000= 7.27 ns , and that's what they announce as well (they called them "GDDR5 7 ns chips")
So despite all the FUD about this again, the GDDR5 is also better at real world latency because it's way faster, latency has to be defined by a certain speed or it doesn't make sense. MS had to pick way faster modules to get an advantage on latency. At 2133 Mhz you can't have both at a reasonnable price, it would have to come down as low as CAS 7 to get under 7ns latency, that kind of DDR3 is probably twice the price or more, compare to what they will have to pay for that kind of modules.
DDR3 is simply not a high end type of memory, it's a really good solution for cheap on the cpu side and you can get really decent latency at moderate speed by thightening the timings, but anyone would replace it by GDDR5 if possible, it's just better memory overhaul.
There's no "massively lower latency" DDR3 in Xbox One, Not even MS is using this argument, because they know they are behind on this too and it would be easily debunked, it's just their supporters that usually don't know anything about hardware, who brag on every forum that the X1 memory is Sooo much better at latency..(funny considering Xbox 360 had GDDR3 for its CPU back then)
Esram is another story and there is maybe an advantage here on very specific tasks, very demanding back and forth type of process, but there s no 8 GB, just 32 MB, and i highly doubt anyone will use eSRAM for CPU tasks, since it's always gonna starve for more on the gpu side.
