It has the best RAM bandwidth and compression done this way makes size irrelivant
To store 1001100101010101
1|0|
0 0
# #
0 0
# 0
---0
---0
---0
1|0_1|0
-----# 1
-----1 #
-----1
-----1
1|0_1|0_1|0_1|0
--------1
--------1
1|0_1|0_1|0_1|0_1|0_1|0_1|0_1|0
-------------------------1
You can compress those 16 bits down to 1 bit and a value stored of 9 at 4 bit or 16/5 compression ratio about 3 to 1 the compression ratio is log(X)/log(2)+1*2^64-X this allows Nintendo to use the speed of the 256GB/s edram without needing 8GB of space. Also Since the Wii U's edram is faster than any ram of the PS4 there is no equivalent on the PS4 for performance. This is then used to compress three 16 bit float
http://en.wikipedia.org/wiki/Half-precision_floating-point_format
values into 1 3 from compressing the 4bit value got from compressing the 5 bit value got from compressing 3 to 1 with one arraylist of stack. In the 2GB of RAM you store a table which calculates all operations some aren't needed because there too big or small to be a 16bit float. 2GB is enough to store all combinations of 16 bit floats. The compressed answer is copied over to edram to be decompressed in order to increase speed you combine five 3 bit answers into one 15 bit answer and add a meaningless two bit 0 so its sixteen bit and can be compressed with three completed values 23 times with the table this makes it so that when you go to copy it over to edram from 2GB its too small to effect computation time. then the computer decompresses the 16 bits you gave it compressed 23 times back up to the right size. This gets you 2Terraflops 16 bit just like the PS4 it just uses a different method. You store Arrays to do the calculation +-B% which each take up 1-2 MB uncompressed of Edram for addition and subtraction +-B%=1+-1/B. To Do Division You do +-B%. All you store with the Table in 2GB is multiplication which takes up 0.75 Gigabytes.
These equations are how you do multiplication Division Adition and Subtraction from these arrays at 2TF
A*B*B%=A+B
A*B*-B%=A-B
(A*B%)*A*-A%=A/B
A*B=A*B
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