New RAM used for noncritical apps
The PlayStation 4 Pro will offer half a gigabyte of extra RAM to game developers, thanks to the addition of 1 GB of memory for nongaming uses such as multitasking, reports Digital Foundry.
"We felt games needed a little more memory — about 10 percent more — so we added a gigabyte of slow, conventional DRAM to the console," said Mark Cerny, lead system architect for the PS4, in a lengthy interview with Digital Foundry. The extra DRAM is different from the console’s existing 8 GB of GDDR5 graphics memory; it’s not meant to be used for games.
Cerny explained that the current PS4 uses part of its fast GDDR5 RAM for multitasking, keeping nongaming apps like Netflix in memory to allow for quick switching between a game and something else. That’s not the best use of the graphics RAM, which is why Sony added the slower DDR3 memory to the PS4 Pro.
"On PS4 Pro, we do things differently, when you stop using Netflix, we move it to the slow, conventional gigabyte of DRAM," Cerny told Digital Foundry. "Using that strategy frees up almost one gigabyte of the eight gigabytes of GDDR5."
Half of the freed-up RAM is available to game developers, boosting the total amount to 5.5 GB. (The existing PS4 offers as much as 5 GB of memory for games.) The PS4 Pro uses "most of the rest" of the extra graphics memory, said Cerny, to draw the console’s interface at 4K resolution — four times the pixels of the current 1080p resolution.
In addition to giving game developers more graphics memory, the PS4 Pro offers faster memory. The 8 GB of GDDR5 RAM in the original PS4 is clocked at 176 GB per second; the PS4 Pro boosts the speed by 24 percent to 218 GB/s. Coupled with a technique known as delta color compression — a feature from AMD’s Polaris GPU architecture that makes more efficient use of memory bandwidth — the speed increase should be very useful for developers, according to Cerny.
The PS4 Pro will be available Nov. 10 in Europe for €399, Japan for 44,980 yen, the U.K. for £349 and the U.S. for $399.