Sony Reveals Additional PlayStation 4 Architecture Details: It Is All About the Speed

Sony: PS4 Will Heavily Rely on GPGPU Technologies

by Anton Shilov
04/26/2013 | 03:45 AM

Sony Computer Entertainment this week revealed additional architectural details about the PlayStation 4 video game console. The company claims that while the semi-custom accelerated processing unit from Advanced Micro Devices inside the PS4 resembles the modern personal computers, it features a number of enhancements made to speed up peak performance as well as make it easier for game developers to simultaneously use x86 and graphics stream processors.

 

Sony PlayStation 4 is based on a semi-custom AMD Fusion system-on-chip that integrates eight AMD x86 Jaguar cores, custom AMD Radeon HD core with unified array of 18 AMD GCN-like compute units (1152 stream processors which collectively generate 1.84TFLOPS of computer power that can freely be applied to graphics, simulation tasks, or some mixture of the two), various special-purpose hardware blocks as well as multi-channel 256-bit GDDR5 memory controller. As it appears, there are a number of enhancements designed to speed up graphics performance as well as make it easier for game developers to use the heterogeneous system architecture of the chip.

“Our overall approach was to put in a very large number of controls about how to mix compute and graphics, and let the development community figure out which ones they want to use when they get around to the point where they're doing a lot of asynchronous compute,” said Mark Cerny, the lead architect of PlayStation 4 system, in an interview with Gamasutra web-site.

The PS4 SoC has three major enhancements not found on today’s PCs (it is unclear whether at least certain of those technologies will eventually make it to the PC, but it is highly likely):


Screenshot from Killzone Shadow Fall, a PS4-exclusive title.

“If you look at the portion of the GPU available to compute throughout the frame, it varies dramatically from instant to instant. For example, something like opaque shadow map rendering doesn't even use a pixel shader, it is entirely done by vertex shaders and the rasterization hardware – so graphics are not using most of the 1.8TFLOPS of ALU available in the CUs. Times like that during the game frame are an opportunity to say, 'Okay, all that compute you wanted to do, turn it up to 11 now',” said Mr. Cerny.

While the PlayStation 4 is very powerful already, there were ways to further boost its performance, but at the cost of increasing complexities for game developers. The company decided that minimal hassles for game designers is more important than additional performance and decided to steak to the current architectural solutions. The benefits of Sony’s architectural decisions will be seen in the PlayStation 4's launch games.

"The launch lineup for PlayStation 4 – though I unfortunately cannot give the title count – is going to be stronger than any prior PlayStation hardware,” said Mr. Cerny.

Sony PlayStation 4 will be launched later this year worldwide.