Pemalite said:
Michael-5 said:
Now I have a question, if Memory bandwidth is only a 5x improvement in the PS4 (38.4 -> 192 GB/s), will that hinder and help the PS4's performance? Is there a linear relationship, or exponential?
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Memory bandwidth is difficult.
Memory bandwidth will have a direct relationship with fillrate, however there comes a point where more memory bandwidth just won't improve anything.
Think of it like this, with memory bandwidth if it is too slow, the GPU has to wait on more data to arrive, that's wasted clock cycles and thus you receive a performance penalty.
Where-as if you have memory bandwidth that is too fast, the GPU has all the data it can possibly handle leaving memory bandwidth wasted, this is a waste of money as you could have gone with tech that is cheaper/slower clocked.
Microsoft and Sony would have done the math on this, same with AMD and nVidia and it seems for a GPU that's around the performance of the PS4's the magic number is around 150-200GB/s.
You also need to keep in mind that consoles are only rendering at 1080P or lower, it's not that demanding anymore so you don't need roughly 300GB/s of memory bandwidth like in high-end PC cards.
All in all, when running similar resolutions the memory bandwidth can have orders of magnitude performance benefits, provided the GPU can keep up and use it, that's not to mention that technology such as 3dc texture compression will save on memory bandwidth right out of the gate.
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What are PC's rendering at, if not 1080P?
How do you find out about all this stuff? Like PS4 needing 150-200GB/s of Memory Bandwidth?
Either way, in the end, PS4 is about 10x as powerful as PS3. I did learn a lot about why, but I never claimed it was more or less then this (well I think closer to 9x, but 9x, 10x, it's about that).
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So do you agree with me about how PS4 games will look better? Like I said increasing the number of polygons, even by a factor of 10x, makes a small difference now, compared to N64 times. However with the larger number of shaders, and higher RAM, PS4 and One can render more objects on screen, with better graphics and texture resolution then a PS3. So PS4 games in comparision to PS3 games, won;t look particularly better, but effects (like sand), and the number of ojects on screen will improve, making game worlds look much more full.
Actually, I hear this is how Watch Dogs works, the PS4 and PS3 game are based off the same engine, but the PS4 game has higher texture resolution, more effects, NPC's, cars, object, etc on screen, etc.
