Captain_Tom said:
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Exactly what I was thinking. People act like DDR3 was cheaper, but in the long run it could easily end up costing more. Especially since they tried to make up for it with costly ESRAM...
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There s a real possibility MS will be able to use DDR4 later in X1 cycle. If their controller is designed to support it and it's very likely it will. There s not much difference between the two standards and the DDR3 they picked is precisely where the DDR4 begins (2133 Mhz)
As for the old debate about latency. X360 never had problem using GDDR3 for its CPU. The whole thing is some kind of urban legend, GDDR latency are really good, in fact GDDR memory are just better memory chips overhaul (that comes with a price), they arent behind in latencies they are just way ahead in base cock and effective bw (cause of the x4 multi).
In PC CPU benchmarks, BW always wins over latency, if you increase the speed of your memory, you increase bandwidth and gain fps, even if you have to loosen the timings. GTA memory benchmarks are a good example
Even if you go from 1600mhz at 7-7-7-19 to 1866 at slower timings 9-9-9-24 you gain fps from the CPU side of things, so now let's imagine going from 2133 Mhz to 5500 Mhz, with equal or even worse timings..it's still gonna be faster. Modern CPU are also highly parrallel in multi core configuration, timings are becoming less and less important, like on the gpu side, BW is everything.
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OMG thank you again! It has been proven many times that higher bandwidth trumps lower latency by a considerable amount. This latency advantage is like most other things MS has been saying: BS.
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No this is nonsense too. The CPU on both these machines will only be using mayube 20 GB?s on both.
The latency can actually make a huge difference, this is why CPU's have MB's of L1, and L2 cache, and adjusting the amount of cache has a HUGE effect on CPU performance. It prevents cache misses that cost hundreds of cycles of wait time while the CPU goes out to main memory.
It also depends on the benchmark. If the benchmark you linked is memory bandwidth limited, then increasing BW will help the most. But not every workload or benchmark is the same.
But I wouldn't worry about the CPU's, where the massively lower latency of XBO's ESRAM over PS4's GDDR5 can really pay off is with the GPU.
