[Reddit] Get your popcorn ready: NV GPUs do not support DX12 Asynchronous Compute/Shaders. Official sources included.

[StrikerX]

This all came about due to Oxide's upcoming DX12 RTS, Ashes of the Singularity. When they released the benchmark, various places found that AMD GPUs had a massive performance gains (partly DX11 driver overhead, partly because GCN's ACEs are doing nothing on DX11), but NV GPUs actually do worse in DX12.
As noted here.

NV fired some pretty fine words at Oxide, dissing their game as not representative of DX12 games, and claiming they had a MSAA bug. Oxide fires back saying the bug is actually in NV's drivers and offered to help them fix it.

They made a nice blog about DX11 vs DX12 where they clarified it and that they were not out to gimp any hardware, but they play fair by the DX12 book.

This escalated on the tech forums, getting heated accusations thrown around, and so Oxide came into the discussion with this bombshell:

Maxwell doesn't support Async Compute, at least not natively. We disabled it at the request of Nvidia, as it was much slower to try to use it then to not.

Followed up with this:

Personally, I think one could just as easily make the claim that we were biased toward Nvidia as the only 'vendor' specific code is for Nvidia where we had to shutdown async compute. By vendor specific, I mean a case where we look at the Vendor ID and make changes to our rendering path. Curiously, their driver reported this feature was functional but attempting to use it was an unmitigated disaster in terms of performance and conformance so we shut it down on their hardware. As far as I know, Maxwell doesn't really have Async Compute so I don't know why their driver was trying to expose that.

I suspect that one thing that is helping AMD on GPU performance is D3D12 exposes Async Compute, which D3D11 did not. Ashes uses a modest amount of it, which gave us a noticeable perf improvement. It was mostly opportunistic where we just took a few compute tasks we were already doing and made them asynchronous, Ashes really isn't a poster-child for advanced GCN features.

Our use of Async Compute, however, pales with comparisons to some of the things which the console guys are starting to do. Most of those haven't made their way to the PC yet, but I've heard of developers getting 30% GPU performance by using Async Compute.

And finally this, they basically challenge NV to prove them wrong.

There is no war of words between us and Nvidia. Nvidia made some incorrect statements, and at this point they will not dispute our position if you ask their PR. That is, they are not disputing anything in our blog. I believe the initial confusion was because Nvidia PR was putting pressure on us to disable certain settings in the benchmark, when we refused, I think they took it a little too personally.

It looks like Oxide is angry at NV since NV tried to make them look like fools despite the problem being with their hardware, so Oxide took it personally and go public.

And now, AMD chimes in! u/AMD_Robert (Robert Hallock):

NVIDIA claims "full support" for DX12, but conveniently ignores that Maxwell is utterly incapable of performing asynchronous compute without heavy reliance on slow context switching.

GCN has supported async shading since its inception, and it did so because we hoped and expected that gaming would lean into these workloads heavily. Mantle, Vulkan and DX12 all do. The consoles do (with gusto). PC games are chock full of compute-driven effects.

Looks like this is escalating, time to prepare the popcorn and see NV's response!

As to why Async Compute/Shaders are so important in DX12 & future cross-platform games:

1. Compute is used for global illumination, dynamic lighting, shadows, physics, post-processing (including even AA). If it can be offloaded from the main rendering pipeline and done asynchronously in parallel, it can lead to major performance gains. As such, GPUs that support it will see major performance uplift and in theory, GPUs that do not support it, will have no benefit, it reverts back to the normal serial rendering of graphics & compute.
2. Async Shaders are vital for a good VR experience, as it helps lower latency of head movement to visual/photon output. I posted on this topic awhile ago: https://www.reddit.com/r/nvidia/comments/3i6dks/maxwell_cant_do_vr_well_an_issue_of_latency/

Because I suspected it may be related to their Async Shader pipeline, now it looks to be confirmed.

For the ELI5/noob/layman/TLDR: click HERE.

Source: Reddit

Spoiler: show

- - - Updated - - -

More stuff in detail here (and a lot of other enthusiast forums): [H]ard|Forum

Spoiler: show

[MENTION=39471]Blastwave[/MENTION] [MENTION=15943]UmerF[/MENTION] [MENTION=8932]Dark Sith[/MENTION] [MENTION=18102]Lord Ammar[/MENTION] [MENTION=4374]Journeys End[/MENTION] [MENTION=25983]AbbY[/MENTION] [MENTION=24535]Ali Kamran[/MENTION] [MENTION=218]CerebralTiger[/MENTION] [MENTION=21647]nafu[/MENTION] [MENTION=8564]AFQ[/MENTION] [MENTION=11130]sherrypizza[/MENTION] [MENTION=5589]devilwing[/MENTION] [MENTION=551]GoldenHawk[/MENTION] [MENTION=72]DSM1[/MENTION] [MENTION=32279]Baghi[/MENTION] [MENTION=23230]sunnykhan[/MENTION] [MENTION=4486]ali tayyab[/MENTION]

 

[rafay22]

Yay to lol hoogia

 

[Ali Kamran]

I don't think it is a major problem for NVIDIA. They can easily fix with new drivers. AMD finally has something to cheer about and if the story is indeed true that NVIDIA does not perform well on DX12 then this will be a huge win for AMD. AMD's GPU share has decreased to 20% and it needs to stay competitive. DX12 can give it a second chance but we all know NVIDIA will come back stronger.

NVIDIA's GPUs are superior and Async Compute can be countered in some way. This is only one benchmark we are talking about here. Let DX12 games roll out and then compare the performance of both companies.

 

[ahmed anas]

If this is true and if Nvidia isn't able to fix the issue by a driver update, Nvidia can simply release a new line of cards early next year by the time dx12 actually comes out and people will still buy Nvidia since it's just soo ahead of AMD right now in the mid/high tier.

 

[StrikerX]

Its a design flaw.

p.s Nvidia hasnt responded to this yet, will be interesting what they come up with :crazy:

 

[Blastwave]

The comments on the thread are golden.

I'm not concern with that. I'm concerned with why a big corporation is allowed a free ride when they lied about the 3.5gb and if they lie about DX12 capabilities again...

Is it Apple-syndrome where they can never do wrong?

I buy my top GPUs with the intention of keeping it for ~3 years. If I had splurged on the Titan X thinking its fine for VR and its excellent for DX12... I would be very very pissed.

Source: https://www.reddit.com/r/pcgaming/c..._popcorn_ready_nv_gpus_do_not_support/culf855

 

[Kane]

Wtff!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[Ali Man]

The comments on the thread are golden.

I'm not concern with that. I'm concerned with why a big corporation is allowed a free ride when they lied about the 3.5gb and if they lie about DX12 capabilities again...

Is it Apple-syndrome where they can never do wrong?

I buy my top GPUs with the intention of keeping it for ~3 years. If I had splurged on the Titan X thinking its fine for VR and its excellent for DX12... I would be very very pissed.

Source: https://www.reddit.com/r/pcgaming/c..._popcorn_ready_nv_gpus_do_not_support/culf855

The people of reddit are morons, couldn't say it any better way.


At the current point in time, these comments are as neutral and sensible as it gets:


From Oxides dev:

Weather or not Async Compute is better or not is subjective, but it definitely does buy some performance on AMD’s hardware. Whether it is the right architectural decision for Maxwell, or is even relevant to it’s scheduler is hard to say.

And this from Johnny boy:

Theoretically, AMD cards should reap greater rewards from DirectX 12 as upcoming games begin to take full advantage of Async Compute Cores, a feature which is supposedly missing from NVIDIA’s line-up. As a result, it’s sensible to believe that AMD’s core architecture features the potential for greater gains. However, DirectX 12 is still an unknown entity and the Async Compute Cores could only be a small factor in the widespread performance numbers. Additionally, the spokesperson for Oxide admitted that Unreal Engine 4 doesn’t properly utilize Async Compute Cores so the difference will be negligible.

NVIDIA’s DirectX 11 implementation is very impressive through optimized drivers meaning their hardware had a long standing history of outperforming AMD on a software and hardware level. Now, AMD is more familiar with DirectX 12, it’s possible the gap could be reduced as NVIDIA gets to grips with the new API. Whatever the case, the true impact of Async Compute Cores is unknown and it’s up to future games to see if this will be a real-world advantage or something restricted to synthetic benchmarks.

Source

 

[Pleasant]

The people of reddit are morons, couldn't say it any better way.


At the current point in time, these comments are as neutral and sensible as it gets:


From Oxides dev:




And this from Johnny boy:



Source

so in short we need to see how many fps difference we are seeing in gaming if thing isnt rosy for nvidia i am pretty sure they will come up with new lineup to counter some way

 

[iampasha]

Damn! i have to buy pascal series card next year and all this is making me a bit nervous...

Sent from my XT907 using Tapatalk

 

[Blastwave]

Everyone with 9xxxx series just got #rekt

#nvidiots

 

[GoldenHawk]

Well to be honest Nvidia hasn't been the dependable jolly green giant we have all come to love as of late this problem of theirs has me seriously worried first it was crappy drivers starting from january till now even windows 10 driver performance is a downgrade from win 8 they cant even fix Sli problems on existing hardware now with DX12 and new hardware problems just piling up to the old ones i think Nvidia will lose consumer confidence in the coming months if they haven't already .

AMD on the other hand is better suited to take charge with their current form of great drivers and the fact that current gen consoles are using AMD hardware giving them an edge on optimization

the tables could turn just saying !

 

[nafu]

well, A shocking update at a very crucial time, Right Before DX12 application on hardware. NVIDIA wholly depending on DX12 performance boost to rulling for another next year. but this clearly changes the stance of NVIDIA, NVIDIA do have Driver optimization, But here The race is for DX12. they only talking Business and nothing.

While Seeing the Benchmark, AMD totally God like Performance, AMD couldn't make there full to its flagship and new series but DX12 update really make win win situation for them. A Happy Ending

 

[UmerF]

This year is already over almost and DX12 games aren't that near anyway. I'll wait for real-world testings to judge this to be honest and even if the current 9xxx series sucks and lacks behind performance by a significant margin the sad truth is it still won't affect NVIDIA sales anyway and as a company in whole.
I'll wait til Pascal is out anyway and see what they have to offer which should be much better and if it is, infact a design flaw then that should be fixed there and current users will be left in the dust with their cards in their hands.

All in all, I could care less anyway. I'm definitely interested to see the upcoming FreeSync monitors and have been considering getting a second gaming monitor to be FreeSync instead of G-Sync so I have both so whenever I jump ships from card to card I can benefit from it both since it's a must have right now with 4K gaming to be able to play smoothly everything maxed out even on low-fps so there is a good chance I might do that but I'm still keen towards Pascal which will be announced early next year InshaAllah and if not then I'll just sell this card anyway and upgrade to another so I'm not affected myself.

 

[UmerF]

On the other hand, this is becoming to look even sexier to me: https://www.overclockers.co.uk/showproduct.php?prodid=MO-090-AC even though the G-Sync version is 100hz instead of 75hz.

 

[Yasir Nadeem]

Screw nvidia dafuq are they doing

 

[sherrypizza]

Its time to throw away the Popcorn
After yesterdays turmoil on a lacking DX12 feature for Nvidia AMD’s Robert Hallock shares that Fury X is also missing a number of DX12 features. The good man replied in a Reddit thread on the DX12 Async shader/compute feature that is missing from NVIDIA’s graphics cards, and then claimed that there is no such thing as “full support” for DX12 on the market today. Which obviously was already known as AMD never claimed full DX12 support on all feature levels with their GCN architecture“I think gamers are learning an important lesson: there’s no such thing as “full support” for DX12 on the market today.” said Robert and continued:

“There have been many attempts to distract people from this truth through campaigns that deliberately conflate feature levels, individual untiered features and the definition of “support.” This has been confusing, and caused so much unnecessary heartache and rumor-mongering.
Here is the unvarnished truth: Every graphics architecture has unique features, and no one architecture has them all. Some of those unique features are more powerful than others.
Yes, we’re extremely pleased that people are finally beginning to see the game of chess we’ve been playing with the interrelationship of GCN, Mantle, DX12, Vulkan and LiquidVR.”
​

When somebody asked what are the aspects of DX12 that the FuryX is missing, Hallock replied and listed them.

“Raster Ordered Views and Conservative Raster. Thankfully, the techniques that these enable (like global illumination) can already be done in other ways at high framerates (see: DiRT Showdown).”
​

So it is simple, currently no graphics card with full 100% DirectX 12 support, that means that some games are to favor AMD and others Nvidia.

I want to add thing here, yesterday Hallock was all over this downplaying Nvidia and evangelizing how good their GPUs are, and now he is taking a step back with these answers on Reddit.It's all marketing mud-fighting and attacking each other these days in-between Nvidia and AMD. Fun fact: on the AMD GPU Tech day for Fury, I myself literally confronted and asked about the DX12 supported feature levels to Hallock, and in this case Hallock himself absolutely refused to give a valid answer at the time as he very well knew that AMD would not fully support DX12 either.
by Hilbert Hagedoorn

 

[UmerF]

[MENTION=11130]sherrypizza[/MENTION], can you please link us to the source you got all that information from? it'll be helpful.

 

[StrikerX]

[MENTION=11130]sherrypizza[/MENTION], can you please link us to the source you got all that information from? it'll be helpful.

Guru3d and all it says is AMD doesn't support dx12 completely which AMD themselves said

Which obviously was already known as AMD never claimed full DX12 support on all feature levels with their GCN architecture

Real issue still is how much of a performance hit Nvidia will take with async compute cause Deus ex/tomb raider/mirror's edge coming out next year utilize it.

 

[UmerF]

Guru3d and all it says is AMD doesn't support dx12 completely which AMD themselves said


Real issue still is how much of a performance hit Nvidia will take with async compute cause Deus ex/tomb raider/mirror's edge coming out next year utilize it.

Exactly as all these are just .. initial reports you can say I guess. I'm interested to see real-world scenario when the games actually hit the market as a final product plus like I mentioned, I could care less .. I'll be moving to Pascal anyway or maybe even jump the ships so whatever
It's not like it's gonna be hard getting rid of 980 Ti in this market, lol.