Quick test: DirectX 12 API Overhead Benchmark results
As you guys know, DirectX 12 is going to greatly free up processor utilization, and thus your games can make more draw-calls with your processor. More efficient usage of CPUs with multiple cores is trivial in the design. We can now test a thing or two out thanks to the 3DMark update released hours ago.
At this very moment with DirectX 11, no matter how many cores your CPU has, the first core does the majority of the hard work for the API, the rest of the cores doing very little. With DirectX 12 (and Mantle), the data-sets and this load will be better distributed and utilized meaning a far more efficient design usage, this removes certain CPU bottlenecks. DX12 is said to be capable of using as many as eight cores and hey, AMD has very nicely priced 8-core processors right ? But how can we test to see what is up and coming ?
Well, even you yourself can check that out @home now. If you own a 3DMark 2013 license and have Windows 10 preview build 10041 (free to download and install as it is a public preview) and have a compatible graphics card with DX12 enabled you can now test and see how huge that overhead always has been with 3DMark. Just make sure you update Windows 10 towards build 10041 which has DX12 support. For the graphics card drivers, wait for the Windows update. The Windows driver that install through the update are DX12 class compatible with respective Nvidia and AMD graphics cards.
The test works by tasking the GPU to draw something on the screen, literally this is what a draw call is, a request from the game engine on the processor to draw and render an object, period. This instruction goes through the API, that API would be DX11, DX12, or AMD's Mantle.
The less efficient the API is in handling the what we explained are "draw calls" from the CPU to the GPU, the fewer objects can be drawn on your monitor. 3DMark now has this test, and will speed up draw calls and objects until the frame rate drops under 30 frames per second (fps) and that is its equilibrium. The result is what we can show as the difference in number of draw calls per API. Our test has been performed at 1920x1080 (default is 1280x720 I think it was), just to make things a little heavier and more representative. Check out these numbers man, specifically in the jump from DX 11 towards Mantle and then DirectX 12. Mantle actually is a notch faster compared to DX12, still ... what a difference.
Intel Core i7-5960X (16 threads) / Radeon R9 290X
Our test system is absed on the following hardware:
- Intel Core i7-5960X (16 threads)
- AMD Radeon R9 290X
- MSI X99S XPower AC
- 16GB GSKILL DDR4-2133 Quad channel
- Corsair Force SSD
The difference in increase draw calls is going to be extraordinary positive. Obviously the results are relative to actual complex rendered frames and frame rates. But any old and or new processor will be utilized so much better. In the end the Windows 10 / DX12 combo is going to make a difference alright, yeah we are excited as man. Scene complexity with many more objects is going to rock hard. I mean overall we are looking at a 15 to 20x draw call increase on any mainstream to enthusiast class processor and what that can do with scene complexity will be very impressive. Also this means very good news for AMD and its APUs and FX processors as well as the entry level Intel CPU SKUs.
Yeah DirectX 12 could be a game-changer (literally) once widely adopted by the software houses, as such we feel this release is going to be EPIC. Go try it out yourself and let us know your results in the forums. You can download the updated 3DMark right here.
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Nvidia does not want to support Mantle.
Nvidia supports Direct X because it is from Microsoft, which is one of their biggest resources.
Senior Member
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My results:
DX11 Single: 1,010,597
DX11 Multi: 985,836
Mantle: 12,108,110
Dx12:: 12,958,613
Intesting to note DX11 multi is actually slower, and for me DX12 is faster than mantle (AMD probably hasn't optimized mantle for 7xxx series as much as the 290 series)
In most tests I see, DX12 is faster then Mantle even on the 290x. I think it has to do with the number of cores, Mantle scales better on a higher number of cores/threads then DX12 does.
Senior Member
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I was thinking "I'm gonna run this benchmark", then I realized I'm on Windows 7 and M$ don't update their old OSes to have new APIs anymore. I haven't used a Windows beta as my main OS since Vista. Which oddly I had no issues with at all after my sound card drivers were fixed to work with it.
Vista and 7 look and function so similarly it feels like I've been using the same OS since 2006. If Win 10 is released in 2016 that'll be a decade of the same look/performance as far as OSes go for me, now I know how Mac users feel.
Senior Member
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I got ~ 1million draw calls boost by dx11 single threaded when going from 1333 9-9-9-24-2t (20gb/s, 65ns) to 2400 10-12-12-31-1t(36gb/s, 41ns)
By multi it was less, ~ 100k calls difference.. Still something

I see dx12 makes a nice boost
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NVidia has DX11 multi-thread rendering while (I think) Amd doesn't have that.
Civilization V was one of the game that hugely benefits NVidia at that time.
For what is worth, here are my result with my 970
We can see NVidia benefits a lot from DX11 multi-thread rendering