So since when the bandwidth for both ESRAM and DDR3 of XBOX One can be lum sum as one total bandwidth,
guess i have to get back to college and check this out with my Computer Science lecturer.
The GPU is capable of accessing both the eSRAM for read and write purposes. It has four channels to that memory. In addition, in parrallel it can also read from or write to the DDR3 memory, and it has four channels to that memory as well.
That is not how memory controllers work. I have explained (to the best of my insight into the technology) how the gpu mmu crossbar works in another thread. I'm not going to do that again.
The 204GB/s number thrown around by ms is completely bogus (and probably corresponds to creative accounting for some rmw cycles inside the gpu caches). At this time, I stick with a maximum achievable bandwidth of approx. 150 GB/s (for some peculair access patterns). Until a REAL ms engineer comes forth and explains the REAL functions of the gpu crossbar, we should take the numbers forwarded by ms pr speak as rumours (or extremely creative accounting).
Why is everyone getting down to the nitty gritty when the big issue is the amount of high bandwidth memory. 32MB/8000MB is 0.4% of the memory pool.
So 0.4% of the Xbox one memory is higher bandwidth than PS4, the other 99.6% of the memory pool is much higher bandwidth on the PS4. In terms of moving texture data, the PS4 has an advantage hands down. Let's cut the BS. Why even bother going further on that front?
Now, MS may have its advantages too. Fast swiching to/from the OS hub, etc. might be benefitted by ESRAM and parallel pools of RAM etc. There is the issue of latency too.
At the end of the day, IMO, PS4 ram choice was better but was a risk. What if GDDR5 didn't take off? What if it was still rediculously expensive? Etc. Was a gamble by Sony and I think it worked, expecially since they were able to double it from 4 to 8 late in the game. Now, if we were comparing 4 GB of GDDR5 to 8+32 DDR3/ESRAM, would be a different story. But we're not. Hands down you gotta give this one to Sony. That and the GPU.
Now things like co processors, OS experience, fluid GUI, server farm support for online gaming experience, bold moves / different experiences (Kinect) etc. Might all go Microsoft's way. Then of course there are the Games (lest we all forget) that are subjective.