Tuesday, 19 April 2016

The PS4K (NEO): Some Notes

Here are some really quick notes based on the new technical data on a supposed PS4K mid-gen refresh that reworks the SoC (and possibly the RAM but I kinda guess that even the same mainboard design and chips they're currently using can probably clock that fast once the SoC's memory controller is poked a bit). I may come back and rewrite this properly but for some off-the-cuff notes, I'll share what I'd already noted on Twitter.

Ye, the free RAM upgrade (seriously, try to find chips that can't do 7GHz out of the box and AMD must have gotten their controller down by now even if that's something they usually go wide on vs nVidia's narrow bus with high frequency) - 224GB/s is the normal figure for 7GHz so maybe they're still not quite up there with the controller but I think that's more likely than making a wider bus. That makes my list as "most current PS4 are possibly one small tweak from being able to be overclocked like that anyway". Same with 911MHz vs 800: ye, most of the chips probably already get made that can hit that. Even the Jaguar cores moving from 1.6GHz to 2.1: not out of the question and certainly what a chip 3 years more mature could probably get away with under the same Voltage lines (ie power constraints: see GTX 950s that released as 90W parts but now are sold as 75W so no PCI-E power connectors required).

So the actual big news is double the GCN blocks than the current PS4. That makes sense for making it so that games can look visibly better on the new hardware and so bother to make this a second unit with software set to work on it slightly differently than the PS4. If you're building a 4K media box (and Sony have to, they make movies and even kinda have that TV division that's been 15 years without making a profit, right?) then that's not a terrible idea. If they're shrinking to 14nm then that's basically totally fine and easy to budget into a reasonably priced SoC at this stage. Hell, if you didn't double the GCN allocation then it'd look a lot like a CPU-underpowered version of next year's AMD APU (because that is getting AMD's next gen CPU cores: Zen rather than the mobile-focussed Jaguar tiny cores and has a modest amount of new GCN blocks).

As I said on that there Twitter: this isn't even that soon for a mid-generation upgrade. It's just last gen was a long one. UK window between xbox & 360 release was 1359 days. Today is the 872th day of PS4. A year from now: 1237 days into the PS4's EU lifespan. If you're going to release a mid-gen upgrade this is when you need to be getting it ready for release otherwise you might as well wait for a PS5 and a full generation with no forcing devs to keep making a lower-end settings config to make sure it still runs on a PS4.

I played GTA V on the PS3 Slim. If that had been a totally solid fps rather than the sub-20 creaking mess that R* managed (because that was all those consoles could hope to deal with for that scope of game)? That sounds like it would be worth that PS3 Slim being $50 more expensive than it was to me. And that's speaking as someone who had to buy the Slim because my OG PS3 died (optical drive) outside of Sony's warranty. My 'new' 3DS doesn't get a lot of use but I'm really glad I've got a much stronger SoC in it than the device launched with, even if only a few games actually make good use of that. The 'new' bit of the price tag was small, the potential benefit from a much faster and slightly more expensive SoC being inside is large.

Will the PS4K mean some games are released that are fine on it and run like junk on the PS4? Definitely. Is that the fault of the PS4K: nope. Play Just Cause 3 or grab this week's release for £45 on PSN of Alekhine's Gun: we're already at the point where PS4 games can run horribly because that's not a cert fail and some devs just don't get to finish their games. Don't like it, don't buy them; but a higher tier just means some people will get to pay to avoid that bad experience, just as you can buy your way into 1080p60 for most games today if you're prepared to pay for a gaming PC.

The current PS4 is a 1080p console, call it the baseline (shader perf per pixel required). The GPU is 1.8TFLOPS to give a very rough "how big is the GPU" metric (as much of gaming is shader perf limited).
You can get a GTX 970 for not that much: 3.5TF (so 2x1080p).
Current premium PC is a 980Ti: 5.6TF (3x).
The new big Pascal is coming (we know what it can do): 10.6TF (6x1080p - beyond 4K with PS4 level image quality on a per-pixel basis)!
It can also do half-precision mode: up to 21.2TF (12x1080p) and that's going so far beyond 4K as to almost hit 8K!

The new PS4K specs would make it a 4.1TF GPU. So that's not only significantly more than the current design but also putting it between PC VR spec (970) and PC hardcore spec (980Ti) - a good place to be in today for a device that'll be running VR in some months and has a new generation of PC GPUs coming with those numbers that are horrifically large now they've finally gotten to die-shrink to 14/16nm after years stuck waiting for a process that could make commercial 300-600 mm^2 chips that large GPUs demand.

You could maybe get some 4K games out of it, in the same way that a few games on PS3 even got to 1080p via lower per-pixel quality. I think many games would prefer to render at 1440p or something and then scale for output and so give you better anti-aliasing. You can also up the level of detail stuff so that PS4K games were on par with a PC release. When my GTX 760 [2.3TF but dealing with 2GB of RAM that really puts pressure on the new engines] is rendering the Division with far less issues of draw in and shadow detail than the console version then the PS4K can definitely benefit from more perf and being able to really push out the LoD issues. Even when hooking it up to a 1080p TV and using a game with some really good anti-aliasing tech already.

As long as Sony force devs to have a decent config file that allows the games to run on the original PS4, I can only see this as a great step for games on consoles. Make it so we have a base game and a config file for each system. Now let future systems patch in their new config file and, assuming compat that I expect them to maintain between x86 and GCN-derived GPUs (or even just the Metal-like not-GL API that perf games code to), we get to a point where it's actually almost zero effort to release a PS5 where you just put in a PS4K disk or load the PSN download up and it renders in 4K native with greater LoD distances and so on. Because of course you can do that: PC gaming has been all about making games that allow the sliders to go to 11 and one day even budget systems can run them like that.

When I play PS2 games, I do it on a PC because almost all of them can be hacked to roughly run to 1080p or beyond with anti-aliasing etc. And those games aren't even aware of this. Much better than using the PS4 to play the exact same game. Consoles need to get better at that because we're already well into the territory where last gen games look ok when "ported" to next gen via nothing much more than LoD tweaks and resolution increases (if you're lucky, they rewrite the lighting code). Let's call it a living archive and give console games an even longer sales tail rather than allowing 1% of games to get a "HD remake" and everything else is left to die.