I’ve confirmed that there are 8 Jaguar based AMD CPU cores inside the PS4’s APU. The CPU + GPU are on a single die. Jaguar will still likely have better performance than the PS3/Xbox 360’s PowerPC cores, and it should be faster than anything ARM based out today, but there’s not huge headroom going forward. While I’m happier with Sony’s (and MS’) CPU selection this time around, I always hoped someone would take CPU performance in a console a bit more seriously. Given the choice between spending transistors on the CPU vs. GPU, I understand that the GPU wins every time in a console—I’m just always an advocate for wanting more of both. I realize I never wrote up a piece on AMD’s Jaguar architecture, so I’ll likely be doing that in the not too distant future.
The choice of 8 cores is somewhat unique. Jaguar’s default compute unit is a quad-core machine with a large shared L2 cache, it’s likely that AMD placed two of these together for the PlayStation 4. The last
generation of consoles saw a march towards heavily threaded machines, so it’s no surprise that AMD/Sony want to continue the trend here. Clock speed is unknown, but Jaguar was good for a mild increase over its predecessor Bobcat. Given the large monolithic die, AMD and Sony may not have wanted to push frequency as high as possible in order to keep yields up and power down. While I still expect CPU performance to move forward in this generation of consoles, I was reminded of the fact that the PowerPC cores in the previous generation ran at very high frequencies. The IPC gains afforded by Jaguar have to be significant in order to make up for what will likely be a lower clock speed.
We don’t know specifics of the GPU, but with it approaching 2 TFLOPS we’re looking at a level of performance somewhere between a Radeon HD 7850 and 7870.
Update: Sony has confirmed the actual performance of the PlayStation 4’s GPU as 1.84 TFLOPS. Sony claims the GPU features 18 compute units, which if this is GCN based we’d be looking at 1152 SPs and 72 texture units. It’s unclear how custom the GPU is however, so we’ll have to wait for additional information to really know for sure. The highest end PC GPUs are already faster than this, but the PS4’s GPU is a lot faster than the PS3’s RSX which was derived from NVIDIA’s G70 architecture (used in the GeForce 7800 GTX, for example). I’m quite pleased with the promised level of GPU performance with the PS4. There are obvious power and cost constraints that would keep AMD/Sony from going even higher here, but this should be a good leap forward from current gen consoles.
Outfitting the PS4 with 8GB of RAM will be great for developers, and using high-speed GDDR5 will help ensure the GPU isn’t bandwidth starved. Sony promised around 176GB/s of memory bandwidth for the PS4. The lack of solid state storage isn’t surprising. Hard drives still offer a dramatic advantage in cost per GB vs. an SSD. Now if it’s user replaceable with an SSD that would be a nice compromise.
Leveraging Gaikai’s cloud gaming technology, the PS4 will be able to act as a game server and stream the video output to a PS Vita, wirelessly. This sounds a lot like what NVIDIA is doing with Project Shield and your NVIDIA powered gaming PC. Sony referenced dedicated video encode/decode hardware that allows you to instantaneously record and share screenshots/video of gameplay. I suspect this same hardware is used in streaming your game to a PS Vita.
Backwards compatibility with PS3 games isn’t guaranteed and instead will leverage cloud gaming to stream older content to the box. There’s some sort of a dedicated background processor that handles uploads and downloads, and even handles updates in the background while the system is off. The PS4 also supports instant suspend/resume.
The new box heavily leverages PC hardware, which is something we’re expecting from the next Xbox as well. It’s interesting that this is effectively how Microsoft entered the console space back in 2001 with the original Xbox, and now both Sony and MS have returned to that philosophy with their next gen consoles in 2013. The PlayStation 4 will be available this holiday season.
