DX12

[GSalden 4,657]

3 hours ago, MikeyOnTheFlightDeck said:

Yep I was at EGLL using DX12 recently and I saw graphics glitching during taxi (e.g. pixels fading upon movement).  Wasn't sure whether it was due to the Inibuilds mod or DX12.  I need to test more elswhere admittedly.  (I'm using a 3070)

Empty your DX cache…

Just open your Explorer, right­-click on the drive you have Windows installed. 

Click Properties. 

Go to the General tab. 

Click Disk Cleanup. 

Mark the DirectX shadercache tickbox.

[MDFlier 2,031]

22 minutes ago, GSalden said:

Empty your DX cache…

Did that help with the problem you had with one PC being different from the other?

[bvdboomen 257]

I had great flights in DX12 with my 1080ti and 8700K.
Vsync is on and set at 50%. That gives me very smooth frames.
The CPU is nicely balanced with very low utilization and also the GPU runs good. Before SU10 the GPU got hammered at 99/100% when using DX11.
My settings are high with some (trees, clouds) on ultra. Terrain LOD is 200.
I must add that I only have flown the simple GA planes but that's what I fly most of the time.

Running the latest Nvidia studio driver.

Edited September 24, 2022 by bvdboomen

[bobcat999 8,484]

We need Steve's DX12 fixer!     The way he fixed up DX10 in FSX was amazing, with cloud shadows and about 100 other things.

[GSalden 4,657]

1 hour ago, MDFlier said:

Did that help with the problem you had with one PC being different from the other?

Yes, that did help …

[Roy Warren 426]

1 hour ago, bvdboomen said:

I had great flights in DX12 with my 1080ti and 8700K.
Vsync is on and set at 50%. That gives me very smooth frames.
The CPU is nicely balanced with very low utilization and also the GPU runs good. Before SU10 the GPU got hammered at 99/100% when using DX11.
My settings are high with some (trees, clouds) on ultra. Terrain LOD is 200.
I must add that I only have flown the simple GA planes but that's what I fly most of the time.

Running the latest Nvidia studio driver.

I have exactly the same setup as you described, except I have a 1660ti   I've just finished two flights and everything was perfect.  One with the Diamond DA62 and one with the default 320 Neo.

The only thing I am not satisfied is the dark cockpits.  In addition to what you show I installed the upgraded GForce Experience. 

I decided that rather than keep on the fence not knowing what to do, I was just going to jump in, all out.  I am well pleased.

Roy

Edited September 24, 2022 by Roy Warren

[Cpt_Piett 4,678]

I think this post from a knowledgeable user at the official forums gives a great explanation of the benefits of DX12:

Quote

DX12 doesn’t change or improve graphics quality at all. That’s not what it does. DX12 allows more direct access to the bare metal hardware vs accessing through a software layer. When implemented properly, this reduces latency.

With DX12, the sim software can talk directly to the GPU without having to talk through the software API that goes through the CPU first. This alleviates the workload on the CPU. That’s why under DX12, people who were previously CPU (main thread) limited are now seeing themselves GPU limited instead.

DX12 also allows much more direct CPU thread management, and more optimized multithreading, making better use of extra cores and threads. Under DX12, you’ll find that your CPU is used much more effectively and more of its free resources are being leveraged than what DX11 is capable of.

https://forums.flightsimulator.com/t/discussion-poll-sim-update-10-1-27-21-0/543730/674?u=cptpiett8113

As for myself I get better CPU multithreading leading to less stutters overall. It's a good idea to have a look in dev mode once in a while to compare the mainthread and GPU frame times. With DX12 I'm much less mainthread limited. I've mostly flown in remote areas since getting the studio driver. But today I'm going to do some tests at larger cities and heavy scenery. I need to know how to tune my graphics settings for these type of scenarios. 

I posted this screenshot in another thread. It's from a flight over remote parts of South Island NZ with a very high terrain LOD and render scaling of 110. Notice the difference between mainthread and GPU frame times. With DX12 I get very high GPU and VRAM usage - which IMO is a good thing. 

 

[Michael Moe 495]

Never understood the values all together . Things has changed regarding focus/none focus screen performance here so i took a screenshot with Fraps .

 

Anyone care to tell what they are seing here ?

Thanks apreciated

Michael Moe

[Cpt_Piett 4,678]

20 minutes ago, Michael Moe said:

Anyone care to tell what they are seing here ?

From the top:

• Current fps is 25
• You're in SDR and using Vsync
• You've set the sim resolution to 4K @ 3840x2160 but rendering at a lower resolution of 2304x1296. Seems you have reduced render scaling in the settings?
• You are currently "Limited by GPU" and you're using DX11 ("PC D3D11")
• Main thread frame time is 22.2ms - the time it takes for the mainthread to render a single frame
• GPU frame time is longer at 26.9ms i.e. at the moment you were GPU limited
• There is a lot of variation in the GPU frame time - min 23.8 and max 51.4 with a median of 38.9ms which is quite long

In other words, at your current settings, it seems your GPU is struggling to keep up with your CPU. 

For people with older GPUs and newer CPUs that often are GPU-limited, DX12 will probably not bring huge advantages. Although DX12 in general leads to better utilization of the CPU, this will not help if the GPU is the limiting factor. 

9 hours ago, Michael Moe said:

Mostly benefits newer RTX2/3 series with DX12?

I am still on 1080TI waiting for a new build still.

DLSS is available from RTX cards and upwards i.e. from the 2000-series. DX12 will work regardless of GPU (others please correct me if I'm wrong). 

Which system did you buy?

Edited September 24, 2022 by Cpt_Piett

[bobcat999 8,484]

18 minutes ago, Cpt_Piett said:

DLSS is available from RTX cards and upwards i.e. from the 2000-series. DX12 will work regardless of GPU (others please correct me if I'm wrong)...

I seem to remember reading anything below a GTX 1080 can't run DX12, but I am struggling to find proof. Not sure about AMD cards. 

[177B 730]

7 minutes ago, bobcat999 said:

I seem to remember reading anything below a GTX 1080 can't run DX12, but I am struggling to find proof. Not sure about AMD cards. 

I have a 1070 and run dX12 with 25+% improvement in FPS.

[rka 916]

IIRC from the GTX 900 series they support dx12 feature level 12.1 which is, again IIRC, what's relevant.

[wiggum 9]

The DX12 bug for 6700 users is really annoying.

[Zimmerbz 168]

Can someone explain what using DX12 should do?  I did a flight in DX12 and DX11 and I didn't notice any difference other than slightly slower frames in 12.  What should be the difference?

[Cpt_Piett 4,678]

4 hours ago, Zimmerbz said:

Can someone explain what using DX12 should do?  I did a flight in DX12 and DX11 and I didn't notice any difference other than slightly slower frames in 12.  What should be the difference?

It won't help much if you're GPU limited, not sure if that's your case. It depends on your hardware; if your CPU outperforms your GPU (e.g. you have an older GPU), the improvements in CPU usage with DX12 might not help much.