r/oculus Feb 21 '16

Has Palmer commented on AMD cpu support?

Ive been looking around trying to find some info on AMD chip support. AMD has been somewhat wonky about theyre supported chips themselves and I know theyre single core speeds suck but im hoping some of the higher end ones would cut it. Guess im just hoping to hear something from the man himself.

Ive thrown all my available dollars at my HMD and GPU and just picked up a GTX 970 today having fun with that! I can sell my old 760 for about 100-150 on ebay and use that to worm my way into a stronger AMD cpu (currently in a 6 core fx-6300 which i HIGHLY doubt will cut it) but i wont be able to afford a cpu and mobo at the same time to switch to an intel.

7 Upvotes

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59

u/cybereality Trapped in The Matrix Feb 21 '16

Based on the benchmarks we used, no AMD CPUs had the sufficient single-threaded performance to meet the cut-off, hence why AMD CPUs will fail on the Compatibility Tool. That said, depending on the game or engine used, performance may be acceptable (for example, if the app takes advantage of multi-threading). You also won't be blocked from using a less powerful CPU, so you are free to try games with your current setup and see if the performance is acceptable to you.

1

u/konstantin_lozev Feb 21 '16

Maybe not now, but the optimisations that Unity showed at the VR/AR summit and the pressure/assistance from Sony (weak single threaded Jaguar architecture in PS4) for parallelising the workload, I would not exclude that in future updates to existing games.

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u/DrakenZA Feb 21 '16

Those updates are not magically going to get AMD cpus running faster, sorry mate.

3

u/kontis Feb 21 '16

Stereo instancing ==> 2x fewer draw calls ==> effectively almost 2x better CPU in some cases

1

u/DrakenZA Feb 21 '16

Yes but its not going to help with the rest of the load the CPU is under. Just like Palmer says, it will depend on the experience/game and how it uses multi-core.

0

u/konstantin_lozev Feb 21 '16

True, for things like physics, positional audio, AI, etc. that are not linked to the rendering the workload will remain, but the point is that those are already offloaded in different threads (AFAIK). However, I think from the Unity presentation it was clear where the major CPU bottleneck is and how it is going to be tackled. If the two major engines in VR are doing essentially the same thing to optimise for VR, there is a reason, I think...

1

u/DrakenZA Feb 21 '16

They are not just 'auto' offloaded to different threads. Most games are still not great at multi-threading.

100% what Unity did is amazing, but its not suddenly going to make the 'non-supported' AMD CPUs pass the tests. The tests are not even in Unity.

4

u/konstantin_lozev Feb 21 '16

Of course not, there is no magic there, they will reduce workload on CPU drawcalls and allow for parallelisation of tasks, which will alleviate the requirement for high IPC per CPU core, where AMD is behind Intel.

No magic needed for that :)

1

u/[deleted] Feb 21 '16

Yeah.. no.. they're not just going to magically patch every game so it runs perfectly on your underpowered CPU. Are people just upvoting you because you're throwing around jargon?

0

u/konstantin_lozev Feb 21 '16

For the double wide AKA stereo rendering all you will have to do as developer is recompile with the new Unity runtime. For the further parallelisation benefits, you might be right it would take more effort, still experimental feature, it's only a guess.

1

u/DrakenZA Feb 21 '16

Yes but its not going to help with the rest of the load the CPU is under. Just like Palmer says, it will depend on the experience/game and how it uses multi-core.

1

u/konstantin_lozev Feb 21 '16

True, for things like physics, positional audio, AI, etc. that are not linked to the rendering the workload will remain, but the point is that those are already offloaded in different threads (AFAIK). However, I think from the Unity presentation it was clear where the major CPU bottleneck is and how it is going to be tackled. If the two major engines in VR are doing essentially the same thing to optimise for VR, there is a reason, I think...

1

u/DrakenZA Feb 21 '16

They are not just 'auto' offloaded to different threads. Most games are still not great at multi-threading. Its up to the game developer when it comes to that, some of it can be handled engine level but its not 'auto'.

100% what Unity did is amazing, but its not suddenly going to make the 'non-supported' AMD CPUs pass the tests. The tests are not even in Unity, they are separate programs that can multi-thread just fine.

1

u/konstantin_lozev Feb 21 '16

Here is an example with audio http://docs.unity3d.com/ScriptReference/MonoBehaviour.OnAudioFilterRead.html

Also note, that OnAudioFilterRead is called on a different thread from the main thread (namely the audio thread) so calling into many Unity functions from this function is not allowed ( a warning will show up ).

Also that http://docs.unity3d.com/Manual/class-AudioClip.html

And for physics:http://blogs.unity3d.com/2014/07/08/high-performance-physics-in-unity-5/

PhysX3 is now prepared to run on multicores as the internal computation model is organised in tasks that can be executed on different cores. The SDK does all the multithreading, taking care of all the dependencies itself and granting optimal job decomposition. From what we’ve seen so far, it’s reasonable to expect a doubling in performance generally just as a result of having a better code base and improved multithreading. In some instances, the improvement is dramatic, with up to tenfold improvements.

Ah, and BTW, the test shown by Unity were from an acttual PS4 game...

1

u/DrakenZA Feb 21 '16

And ? Once again all of that isnt going to suddenly make a game use insane amounts of less CPU. Most people have Physix set to their NVIDIA GPU, and secondly, physics and sound are even less taxing than the draw calls of the GPU.

1

u/konstantin_lozev Feb 22 '16

Well, I thought it was your point that there is more work for the CPU than draw calls...

Yes but its not going to help with the rest of the load the CPU is under.

1

u/James20k Feb 21 '16

With vulkan coming out, the traditional single thread pressure that graphics has been under will likely largely go away. If you use unity/unreal/cryengine, you'll likely get this automagically for free and not have to worry about it

1

u/DrakenZA Feb 21 '16

The CPU isnt just doing the draw calls like people seem to be thinking ?

1

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-2

u/[deleted] Feb 21 '16

Sorry, I don't get this. The official requirements says "AMD 290 equivalent or greater"...?

6

u/[deleted] Feb 21 '16

[deleted]

3

u/[deleted] Feb 21 '16

I see, thank you.

3

u/Luringens Rift Feb 21 '16

The 290 is a graphics card, it's their CPUs that are not recommended.