The DirectX 12 Performance Preview: AMD, NVIDIA, & Star Swarm
by Ryan Smith on February 6, 2015 2:00 PM EST- Posted in
- GPUs
- AMD
- Microsoft
- NVIDIA
- DirectX 12
About a year and a half ago AMD kicked off the public half of a race to improve the state of graphics APIs. Dubbed "Mantle", AMD’s in-house API for their Radeon cards stripped away the abstraction and inefficiencies of traditional high-level APIs like DirectX 11 and OpenGL 4, and instead gave developers a means to access the GPU in a low-level, game console-like manner. The impetus: with a low-level API, engine developers could achieve better performance than with a high-level API, sometimes vastly exceeding what DirectX and OpenGL could offer.
While AMD was the first such company to publicly announce their low-level API, they were not the last. 2014 saw the announcement of APIs such as DirectX 12, OpenGL Next, and Apple’s Metal, all of which would implement similar ideas for similar performance reasons. It was a renaissance in the graphics API space after many years of slow progress, and one desperately needed to keep pace with the progress of both GPUs and CPUs.
In the PC graphics space we’ve already seen how early versions of Mantle perform, with Mantle offering some substantial boosts in performance, especially in CPU-bound scenarios. As awesome as Mantle is though, it is currently a de-facto proprietary AMD API, which means it can only be used with AMD GPUs; what about NVIDIA and Intel GPUs? For that we turn towards DirectX, Microsoft’s traditional cross-vendor API that will be making the same jump as Mantle, but using a common API for the benefit of every vendor in the Windows ecosystem.
DirectX 12 was first announced at GDC 2014, where Microsoft unveiled the existence of the new API along with their planned goals, a brief demonstration of very early code, and limited technical details about how the API would work. Since then Microsoft has been hard at work on DirectX 12 as part of the larger Windows 10 development effort, culminating in the release of the latest Windows 10 Technical Preview, Build 9926, which is shipping with an early preview version of DirectX 12.
GDC 2014 - DirectX 12 Unveiled: 3DMark 2011 CPU Time: Direct3D 11 vs. Direct3D 12
With the various pieces of Microsoft’s latest API finally coming together, today we will be taking our first look at the performance future of DirectX. The API is stabilizing, video card drivers are improving, and the first DirectX 12 application has been written; Microsoft and their partners are finally ready to show off DirectX 12. To that end, today we’ll looking at DirectX 12 through Oxide Games’ Star Swarm benchmark, our first DirectX 12 application and a true API efficiency torture test.
Does DirectX 12 bring the same kind of performance benefits we saw with Mantle? Can it resolve the CPU bottlenecking that DirectX 11 struggles with? How well does the concept of a low-level API work for a common API with disparate hardware? Let’s find out!
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B3an - Saturday, February 7, 2015 - link
Thanks for posting this. This is the kind of thing i come to AT for.Notmyusualid - Sunday, February 8, 2015 - link
And me.dragosmp - Saturday, February 7, 2015 - link
Looking at the Dx11 vs Dx12 per core load it looks like the per-core performance is the limiting factor in Dx11, not the number of cores. As such, CPUs like the AMD's AM1 & FM2 platforms with low per-core performance would benefit from Dx12 more than Intel's CPUs that already have high IPC. (It may be that even the FX may become decent gaming CPUs with their 8 integer cores and not limited by 1-core turbo)guskline - Saturday, February 7, 2015 - link
Thank you for a great article Ryan.okp247 - Saturday, February 7, 2015 - link
Cheers for the article, Ryan. Very interesting subject and a good read.There seems to be issues with the AMD cards though, especially under DX11. Other testers report FPS @ mid 20's to early 30's in 1080P extreme settings even with the old 7970 under Win7/DX11.
The power consumption is also quite low. 241 watts for 290X with 6-core i7, when Crysis 3 pulls 375 also with 6-core i7 in your original review of the card. The card seems positively starved ;-)
This could be the OS, the graphics API or the game. Possibly all three. Whatever it is, it looks like a big issue that's undermining your test.
On a completely different note: maybe you could get the developer to spill the beans about their work with both APIs? (Mantle and DX12). I think that would also be a very interesting read.
OrphanageExplosion - Saturday, February 7, 2015 - link
Yup, this is the big takeaway from this article - http://images.anandtech.com/graphs/graph8962/71451...AMD seems to have big issues with CPU load on DX11 - the gulf between NVIDIA and AMD is colossal. Probably not an issue when all reviews use i7s to test GPUs, but think of the more budget orientated gamer with his i3 or Athlon X4. This is the area where reviews will say that AMD dominates, but NOT if the CPU can't run the GPU effectively.
ColdSnowden - Saturday, February 7, 2015 - link
This reflects what I said above. AMD radeons have a much slower batch submission time. Does that mean that using an Nvidia card with a faster batch submission time can lessen cpu bottlenecking, so perhaps Guild Wars Two would run better with an nvidia GPU as my FX 4170 would be less likely to bottleneck it.ObscureAngel - Saturday, February 7, 2015 - link
Basically AMD now requires much better CPU than nvidia to render the same "drawcalls"I benchmarked my self recently my Phenom II X4 945 OC 3.7GHZ with my HD 7850 vs GTX 770.
Obviously GTX 770 outperform my HD 7850.
Altough i benchmarked star swarm and games where my GPU usage was very below 90% which means i was bottlenecked by the CPU.
Guess what:
Star swarm: AMD DX11: 7fps, Nvidia DX11: 17fps AMD Mantle: 24fps.
I tested Saints Row IV where i get all the time bottleneck with my AMD card where i get all the time more frames more close to 30 than 60, and with GTX 770 i get more 60 than 30.
Even NFS Rivals i have drops on GPU usage to 50% in some locations and that causes drops to 24fps.
With nvidia again, i have 30 rocking stable, unlocking the framerate i have 60 most of the time and where i drop to 24fps due to my CPU with nvidia i have 48fps.
Its not a good example since the GTX 770 is far more powerfull, but you have more proofs with weaker nvidia GPUS in low end cpus really improve the performance comparing to AMD cards that seems to require more power.
I try to contact AMD but i nobody replied ever, i even register in GURU3D since there is a guy that works on AMD, and he never replied, same goes to many persons there are just fanboys and attacked me instead of trying to make pressure for AMD to fix this.
I'm serious worried with that problem, cause my CPU is old and weak, and the extra frames that nvidia offers in DX11 is really big.
Dispite the fact that DX12 is very close to release, i am pretty sure that many games will continue to be released in DX11, and the number of games with mantle it just fit in my hand.
So i am thinking in selling my HD 7850 and buy the next 950ti just because of that, its far more economic than buy a new CPU and motherboard.
I already know this problem for more than 6 months, tried to convince everybody and trying to contact amd, but i am alway attacked by fanboys or get ignored by AMD..
So if AMD reply to me, maybe they dont like my money.
Altough nothing is free, the DX11 optimizations on Nvidia makes eat more Vram and in some games like dying light and ryse i notice more stuttering and sometimes more time to load textures..
Same goes if you use mantle, it eats more vram too.
I expect that DX12 will need more Vram too.
If 2gb is getting short lately prepare that will get shorter if it will ear more vram as Nvidia DX11 and AMD Mantle.
Regards.
okp247 - Saturday, February 7, 2015 - link
I think the nVidia cards are actually being gimped as well. On Win7/DX11 people are reporting 70-80 FPS @ extreme settings, 1080 with the two top 900-cards on everything from old i5's to FX's.They are just not being hurt as much as AMDs, maybe because of more mature drivers and/or different architecture.
Ryan Smith - Saturday, February 7, 2015 - link
Please note that we're using the RTS demo. If you're getting scores that high, you're probably using the Follow demo, which is entirely different from run-to-run.