Anybody think 8 gb of GDDR5 is a mistake for PS4

[drkohler]

fordy said:

That's highly debatable....GDDR5 is faster, but also has a much higher latency than DDR3. It's prefixed with "G" for a reason, because the high latency doesn't affect a highly parallel GPU as much, due to it's ability to process vast more amounts while it waits for a memory fetch.

I wish people would stop praying the "latency mantra". IT IS FALSE.

We are living in the days of high performance, cache driven memory accesses. Long gone are the days when the CPUs grabbed data from main memory one variable/one code line at a time, and long gone are the days when programmers coded their source with pointer arithmetics and local variables. Nowadays, "ugly" programming is what is called for (large fixed-size arrays for variables, global variables and routines grouped according to access probhabilities, etc). What this means that programmers no longer have the cpu in mind, they "program for the memory controller" for the optimum case.

Why? Good memory controllers use longest possible burst modes whenever possible - this means that your cpu/gpu has close to 100% cache hits for code and very high percentages for hitting data in the data cache. Hence memory latencies of the main memory are almost irrelevant (provided you program "ugly"), but memory throughput becomes decisive. And the gddr5 n the PS4 wins hands down against any other solution.