RibbedHero
Member
The official specs are in for the PlayStation 4 and what we have is, by and large, confirmation of existing DigitalFoundry stories - with one outstanding, exciting exception. At the PlayStation Meeting yesterday, Sony revealed that its new console ships with 8GB of GDDR5 RAM, not the 4GB we previously reported. It was a pleasant surprise not just for us, but also for many game developers out there working on PS4 titles now and completely unaware of the upgrade - a final flourish to the design seemingly added in at the last moment to make PlayStation 4 the most technologically advanced games console of the next gaming era.
From an engineering perspective, it's a remarkable achievement. Sony itself doesn't fabricate memory, it buys from major suppliers who advertise the parts available months (sometimes years) ahead of delivery, so we have a decent idea of what options the platform holders have on the table in creating their next-gen systems. The GDDR5 memory modules - the same used in PC graphics cards - are only available in certain configurations, with the densest option available offering 512MB per module. The startling reality is that unless Sony has somehow got access to a larger chip that isn't yet in mass production and that nobody knows about, it has crammed 16 memory modules onto its PS4 motherboard. To illustrate the extent of the achievement, Nvidia's $1000 graphics card - the GeForce Titan - offers "just" 6GB of onboard GDDR5.
The availability of these modules has also been something of a moving target throughout the development of PlayStation 4. In many ways, the genesis of the new console has been an exercise in Sony learning from the harsh lessons brought about by the PS3's custom architecture. The split RAM memory pool didn't work out so well and a unified RAM set-up was always considered a must for the new console. Early rumours suggested that GDDR5 availability could even limit PS4 to just 2GB of memory, with 4GB at one point looking rather optimistic. What changed at Sony and encouraged them to go all out with its final design is not clear, but the chances are it would have been well aware of the RAM advantage offered up by its upcoming Xbox competitor, which - certainly up to its beta hardware at least - features 8GB of more bandwidth-constrained DDR3. What shouldn't be understated is the amount of extra cash this is going to add to PlayStation 4's BOM (bill of materials) - this is an expensive, massive investment for the company.
These two figures in combination also confirm that the graphics hardware runs at 800MHz, as we previously revealed. The mooted 176GB/s bandwidth for the GDDR5 RAM is also now official, suggesting a speed there of 5.5GHz effective - in line with most current Radeon graphics cards. Previous information had suggested that Sony would be splitting GPU resources between rendering and compute functions (VGLeaks suggesting a 14/4 compute unit split between them in its SDK document leak) but the official spec talks of a unified 18 CUs, which "can freely be applied to graphics, simulation tasks, or some mixture of the two". The divide appears to be gone, and devs can apply available power as they see fit.
There was also talk of a new processing module in the PS4 hardware designed to handle tasks like background downloading. Our sources suggest a low-power ARM core designed to handle "standby" tasks along these lines, while the console also saves the current gameplay state when the system is closed down, meaning instant access to the last game you played when you power up again. OS tasks and resource allocation remain unknown (512MB or thereabouts was discussed with developers) but we now have some idea of what this system can do: Sony talks about running a web browser "and other applications" during gameplay.
But similar to that underwhelming PlayStation showing two generations ago, we remain very hopeful: there's a sense that the power is there, that we've only seen the vaguest of hints of what it's truly capable of - and that it'll take time for game-makers to fully understand quite what to do with the new tools they have available. However, from what was shown last night the slightly worrying reality is that in the short term we're looking at games and demos either already running on PC, or with equivalents available now that simply look better.
A lot more in the full article.
http://www.eurogamer.net/articles/df-hardware-spec-analysis-playstation-4