Lighting of Killzone: Shadow Fall Slides

The GPU can't be fully utilized on graphics alone. They'll slot in some compute tasks whenever they can thanks to the 8 ACE.

There is no significant extra power that can be used this way. The extra power is minimal. I can almost guarantee you developers will be using compute in ways that use gpu resources that otherwise could have been used for graphics. They will do so because the cpu is so underpowered. My guess is maybe there is an extra five percent of free gpu time that can be used for compute before you have to start taking away power that could be used for graphics. It is a shame that this game has to run on such an underpowered cpu.
 
There is no significant extra power that can be used this way. The extra power is minimal. I can almost guarantee you developers will be using compute in ways that use gpu resources that otherwise could have been used for graphics. They will do so because the cpu is so underpowered. My guess is maybe there is an extra five percent of free gpu time that can be used for compute before you have to start taking away power that could be used for graphics. It is a shame that this game has to run on such an underpowered cpu.

they will use cycles when the gpu would normally be stalled & running compute at that time it's not taking anything from the graphics.
 
they will use cycles when the gpu would normally be stalled & running compute at that time it's not taking anything from the graphics.

From what I have read, there are normally not as many of these cycles as we would hope. GPUs are already very efficent and at most there are a small number of these free cycles. My guess is maybe five percent of GPU time. This will not be enough for developers, so they will leech graphics power.
 
From what I have read, there are normally not as many of these cycles as we would hope. GPUs are already very efficent and at most there are a small number of these free cycles. My guess is maybe five percent of GPU time. This will not be enough for developers, so they will leech graphics power.

Even if it's just 5% of the GPU that's 92 GFLOPS of compute left over that's not being taking away from the CPU's 102.4 GFLOPS so think about that.
 
What is very interesting is that the developer says that the GDDR5 memory really gives the system "its wings", and lauds the immense 176GB/s of bandwidth available. However, it's not a bottomless pit of unlimited throughput - efforts still need to be made to use small pixel formats in order to maximise performance. Bearing in mind that the vast, unified memory pool of high-bandwidth RAM is one of the key advantages PS4 has over PC and the next-gen Xbox, it'll be interesting to see how multi-platform projects cope.

I found that part interesting, if GG are already maxing out the 176GB/s GDDR5, multiplats are going to struggle to match it on PC (for the time being) and Durango.
So devs might have to use lower res textures on Durango as they only have 68GB/s to work with (I don't think the 32MB of ESRAM would help much with texture streaming?)
 
I found that part interesting, if GG are already maxing out the 176GB/s GDDR5, multiplats are going to struggle to match it on PC (for the time being) and Durango.
So devs might have to use lower res textures on Durango as they only have 68GB/s to work with (I don't think the 32MB of ESRAM would help much with texture streaming?)

Why would they? Multiplat devs would typically target the lowest common specs...I guess this is what they have learned this gen with PS360.
 
But not last gen, where Xbox games often had better textures that their GC/PS2 counterparts.

And even this gen, we saw a few games with slightly better textures on one machine or the other - either due to more disk space on PS3 or more available memory on 360 (especially when the PS3's system reservation was much larger than it is currently)

So I hardly think they'll hold back the PS4 version of titles to keep parity with Durango, especially when they'd already have higher quality textures ready for the PC version. Using higher res textures if the platform can support them, is not complicated to implement; unlike say using higher geometry models on PS4 or something.
 
Whatever makes it easiest for devs is what'll happen. I think that's PC+PS4 and Durango on the other side. Multiplats on PC will be fine, with enthusiast level GPUs easily hitting 176gb/s vram. Though I dont think 3rd parties will push past 4gb or so too much on PS4. The 'medium' to 'medium high' PC setting could essentially be Durango's target.
 
Why would they? Multiplat devs would typically target the lowest common specs...I guess this is what they have learned this gen with PS360.

Multi-plat are usually better on 360 because it's easier to work on it than on PS3 so I don't see why devs should not targeted PS4 "better" specs if they make their work easier.
 
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I found that part interesting, if GG are already maxing out the 176GB/s GDDR5, multiplats are going to struggle to match it on PC (for the time being) and Durango.
So devs might have to use lower res textures on Durango as they only have 68GB/s to work with (I don't think the 32MB of ESRAM would help much with texture streaming?)

Why? Even midrange PC GPUs have around 176GB/s throughoutput or more. The CPU doesn't need as much but high-end PCs should have around 27-3xGB/s CPU <-> System RAM. GPU <-> VRAM upwards 300GB/s depending on which graphic card. Btw IIRC the PS4 CPU cant read/write faster than 20GB/s to the PS4 RAM.
 
^^^
And GG used "only" 3GB.
If the OS is at 512mb as DF says then there are still 3GB left to be used either for video or system memory.

Edit.

I checked Steam Surveys and apparently 0.69% of users have 3072MB of VRAM (April 2013)
7% have over 2GB.
 
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Yeah, KZ4 isn't tapping the extended RAM yet, so there's nothing on show that PCs can't match and surpass.
 
No doubt PC can/will match and surpass PS4 but how many games require 3GB of video memory on PC nowadays?
 
Yeah, KZ4 isn't tapping the extended RAM yet, so there's nothing on show that PCs can't match and surpass.
What a PC with a discrete GPU may not match that easily, is the (for KZ4 relatively small so far) amount of 128MB of RAM shared by the GPU and CPU. This will allow lower latency access than on traditional PC architectures (where this has to go over PCIe and is usually done with a page locked area in host memory which isn't known for best memory performance characteristics neither).
 
What a PC with a discrete GPU may not match that easily, is the (for KZ4 relatively small so far) amount of 128MB of RAM shared by the GPU and CPU. This will allow lower latency access than on traditional PC architectures (where this has to go over PCIe and is usually done with a page locked area in host memory which isn't known for best memory performance characteristics neither).

128mb isnt much really, You can swap twice as that via pcie 3.0 in 16ms.

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No doubt PC can/will match and surpass PS4 but how many games require 3GB of video memory on PC nowadays?

More curious is why they have so many lod pop-in problems with such high video memory amount. They had shadow pop-in 5 meters from player in the demo.
 
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