dx11 vs dx12 performance , not some form of excuse but some info :)

[zzzfrofzzz]

at first , i don't wont to find excuse for issues on witcher 3 next gen update .
yes indeed feel RT features on this update a bit broken , but about perf on DX11 and DX12 , be alert on some points .

as CDPR dev team said , on DX12 they 've add some improvements graphics . to be fair the diference between dx11 and dx12 isn't just RT features .
one thing you can see directly on DX12 version , with SSR technologie , like as on Cyberpunk reflexion works on an other way on DX12 and DX11 .
like as SSR , there's more minors and hidden improvements on DX12 version . so when you see some random vids benchmarks DX11 vs DX12 they may not be revelant or accurate as intended .

to resume utility on DX11 're not the same as DX12 .

my final even this update quite well managed from CDPR with all those technical issues , we need to feedback what's feeling on issues and not follow some trend loving bashing , or pop up click bait vids ^^ .

one major in my issues case with DX12 , the lag in-game : its awfull . the camera seems a bit buuged on DX12 build , on DX11 build no issues with the camera

 

[Lutsky13]

also, DX12 version uses HBAO+ instead of SSAO

 

[Stas25]

dx12 uses this with rtx enabled or am I wrong? and besides, they removed MSAA

 

[Lutsky13]

dx12 uses this with rtx enabled or am I wrong? and besides, they removed MSAA

without RT. it's still called SSAO in settings menu, but if you compare some shots with dx11 or 1.32 buid you'll see its HBAO

 

[bartic]

Those differences between DX11 and DX12 should be better explained, communicated by CDPR.

I don't use RT, but should I use DX11 or DX12?

With DX12 I have glitches on water edges with Texture Quality set on Ultra and minor FPS looses.

I thought DX12 is only for RT or DLSS but it looks like there are more under the hood.

With DX11 I can use graphic mod with Ultra++ settings.

GTX1080
i7-8700k

 

[zzzfrofzzz]

Those differences between DX11 and DX12 should be better explained, communicated by CDPR.

I don't use RT, but should I use DX11 or DX12?

With DX12 I have glitches on water edges with Texture Quality set on Ultra and minor FPS looses.

I thought DX12 is only for RT or DLSS but it looks like there are more under the hood.

With DX11 I can use graphic mod with Ultra++ settings.

GTX1080
i7-8700k

the 2 main issues now
1) as you said no statement official from CDPR about the difference dx11 vs 12 , just an announce explaining on dx12 there's fsr / dlss / RT features with minors improvements .
2) bad performance and more technical issues on DX12

if we have more info , players may be more focus on the benefits gain / lost for visuals aspects .
like i said it always welcome to community players making benchmarks but if we don't know where to look , all benchmarks become not accurate .

like as benchmarks vanilla buid vs NG dx11 build vs NG dx12 build
only the live stream showcase about NG withcher update , we get more info on some aspect than the patch note update .
what the patch note not telling us , player
- on NG witcher build ,they increase quality on some few old default setting ( they' done the same on Cybperpunk 2077 patch 1.5 and 1.6 )
- they add some mods community like as HD rework mods , but nobody know if they completed those mods / debugged ( keep in mind HD reworks having a lot of bug and don't cover all zone and aspect of the game , ..)
...
...

as a player , i only notice some change , improvement when playing the game
for example ( may be its just a placebo effect xD )
the impact on ultra+ setting on dx12 not feel the same as dx11 build
in case i set all setting on ultra+ ,
on dx11 build , switching shadow quality ultra+ to high ,not may make any difference in motion in game
on dx12 build , switching shadow quality ultra+ to high , you feel a bit something is off , to be like as dx11 build we need to set at ultra
playing at 1080p , but may be at upper resolution scaling we can't notice the difference
( visual feedback on 1080p not feel the same way as 4K display ^^ =

 

[lefouduroi.pr]

I switched back and forth before the hotfixes and I personally could not see any differences.

That being said, I did not do an exhaustive testing session, but Alex from Digital Foundry did...

He did not see anything very conclusive from his side neither, so I would tend to agree with him that if, in fact, there are differences, they are marginal at best and can not explain the discrepancies in performances.

That being said, I agree also that CDPR should explain those differences, so that we can better understand it and possibly come to terms with it.

There are surely optimizations to be done, though. Just adding some RTX GI options would be great since the other RTX options are not too frame hungry. It would be great to use a softer implementation of the GI to have access to Reflections and Shadows, without the full 60-70% loss in performances.

Just like I was able to use some forms of RTX in CP2077 on a 2080s. And I know very well that the 2080s is "not really" an RTX card, but it could get away with some implementations like CP2077, Metro Exodus, etc...

EDITED here for precisions: Regardless of the possible visual changes between DX11 and DX12, we can still observe a truly atrocious CPU usage on DX12, which leads to a bottleneck leaving the GPU underutilized. That is not up for debate, just a fact of the state of the optimization. This needs to be resolved in order for players to have their "natural" bottleneck once the issue is resolved. That means full thread utilization. It is not normal that people experience that much of a CPU crunch even with 12900k for example, leaving tons of GPU power on the table.

 

[Martind_Forlon_]

I'm quite curious to learn more about this thread topics ... bcs it seems, there is not much info about DX11 vs DX12 presented (especially official info). My latest experience with 4.01 is that on my nonRT card (1070 Ti) in FullHD resolution is play more smoother (feeling) with DX11 and could be also, that is game running more stable ... but this are just very early observations. For DX11 play on ultra+ (vsync on, space screen reflections high) and capped fps (60) I do not drop below 55 (not even in crowdy areas in Novigrad).

 

[A.P.P.]

I didn't understand anything from OP's post... :/

 

[John_Russell]

If properly programmed DX12 will always outperform DX11. Key words "properly programmed" ..... Witcher 3 Next Gen is not properly programmed for DX12 and is not multi-threading properly causing the two main threads to be CPU limited and banging off 100%. Once they fix that issue (and it might be awhile) then you'll see DX12 outperform the DX11 version.

For those who are interested in the nuts and bolts of proper CPU threading here is an article on the Vulkan website. Both Vulkan and DX12 use the same threading model meaning it's up to the game engine code to do the multi-threading unlike DX11 where it's built into the API

https://vkguide.dev/docs/extra-chapter/multithreading/