| ethomaz said: The CPU in PS4 can't do graphic tasks and it don't need to share RAM with GPU... it is all unifed. |
You might rephrase that statement. The point is there is only one address bus to ram, so yes, cpu and gpu "share ram", all of it...
This is essentially the point of NextBox using edram memory. The gpu can talk to the edram while somebody else can talk to the main ram, at the same time - different address busses. We will see how developers are actually going to use the edram. For starters, my suspicion is that developers will simply use the edram as a frame buffer and call it a day..
Of course the PS4 could also have edram like NextBox. Apart from getting really expensive at some point, this would obviously increase performance. However, since you have two memory pools now. you the developer has to take care of managing the two pools efficiently. Sony went for a very expensive, easier to handle single memory pool, MS went with a very cheap memory pool, and harder to handle small expensive memory pool. The nd result will be the same performance for both consoles, give or take an fps, once developers figured it all out.
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