nVidia 471.96 and DXGI_DEVICE_HUNG resolved

[Ray Proudfoot 8,954]

Just to clarify things for everyone I now have TdrDelay = 60 and TdrDdiDelay=60 both set as DWORD.

[srcooke 52]

Explanation of DWORD & QWORD , worth a read !

[Ray Proudfoot 8,954]

Thanks Stephen, good read. This bit caught my eye... "

However, it does not work like that. If a program, service, or application is programmed to read only a certain type of word, then only that WORD value could be registered. Using a different word would not only make it useless, but there is also a chance of corrupting the Operating System by introducing unexpected System Registries. Hence, it is only wise to use the same type of word recommended by Microsoft for the purpose you intend it for."

Given this TdrDelay is essentially an unofficial hack we don't have any recommendation from Microsoft. Or do we? Have they said anything about this DXGI_DEVICE_HUNG problem given it's not limited to P3D.

Anyway, I'm now enroute from EGCC to Kaastrup so hopefully it will be a problem-free flight.

[Whenmaker 23]

Hi Ray,

today i changed the QWord" TdrLevel=0 to "TdrDdiDelay=60 and TdrDelay=60".

Fired up P3Dv5 and got that "Device_Hung" almost immediately. I think i'll change it back to the "TdrLevel0", because everything runs fine with this option..

Regards

[Ray Proudfoot 8,954]

@Whenmaker, did you reboot before starting P3D? And you created DWORD entries, not QWORD?

[Whenmaker 23]

Sure i did.

[Whenmaker 23]

Could it be that Qword was wrong and i should try Dword instead?

[Ray Proudfoot 8,954]

Just now, Whenmaker said:

Could it be that Qword was wrong and i should try Dword instead?

Have you not read the earlier posts? DWORD, not QWORD must be used.

My flight is 47mins in and it's fine so far.

[Whenmaker 23]

Thanks for clarifying it to me, i'm a bit confused.

[psolk 3,040]

Honestly, trying to make heads and tails of this thread and the "potential" fix makes me very pleased I'm still on 4.5 with no issues 🙂  I can't imagine LM's commercial customers paying millions for this platform are dealing with these issues.  Is it strictly a consumer PC issue? You would think with their commercial audience this thing would be rock solid unless we are just Beta testing for them 😉  

Will be interested to see once this is resolved definitively and what the actual fix is but until then I'm still very apprehensive to make the jump.  

4.5 has become like FS9 to me.  Rock solid, just works and all my add-ons are available to me.  "Hoping" that's what 5.2 becomes in time but right now it still seems to be suffering some growing pains. 

 

[RXP 2,338]

@Ray Proudfoot

It is an officially documented MSFT registry. The link to the documentation is included in the post I've linked to page 3:

On 9/14/2021 at 8:42 AM, RXP said:

I just wanted to add my 2 cents about the registry tip posted on page 2.

I used to have this problem:

Quote

From time to time, my Win10 system would just halt with a black screen with no other recourse than powering off. It is very frustrating and you never know what damage to your files will result out of this [...] When you’re using a HDD and you enable sleep mode, it can take more than 2 sec. to wake up and during that time, at least on my test system...

More details here:

PSA: Solution to HDD and NVidia causing Win10 System Halt with Black Screen

Here is the MSFT doc:

https://docs.microsoft.com/en-us/windows-hardware/drivers/display/tdr-registry-keys

[SteveW 1,792]

On 9/28/2021 at 4:04 PM, SteveW said:

I have a PC here with stock P3D v4 and DXGI_DEVICE_HUNG comes up when the Vehicle window is displayed in the Scenario screen, any aircraft, and the sim closes. That won't be worked around by the registry hack. Changing the Nvidia driver version cures it. There's many ways to get the problem so what might work for one might not work for another.

From my earlier post, no amount of trying Tdr settings in the registry fix this, also clearing out temp files and DX cache does not cure it. This happens every time the scenario window is shown. I can stop it by removing the "Sim" value in the default flight Prepar3D_Default.fxml:

        <Section Name="Sim.0">
            <Property Name="Sim" Value=" " />
            <Property Name="Descr" Value=" " />
        </Section>

P3D complains there is no default vehicle but the scenario screen completes without the hang. This is one of many possible problems that result in the hang. Not all hangs can be resolved with the Tdr entries in the registry.

The only way to stop the problem is to install an older Nvidia driver. I happened to have kept a few older versions, installing 451.67 stops this particular hang. In this instance it is on P3D v4.5 and 2080Ti.

Edited October 7, 2021 by SteveW

[psolk 3,040]

10 minutes ago, RXP said:

@Ray Proudfoot

It is an officially documented MSFT registry. The link to the documentation is included in the post I've linked to page 3:

Here is the MSFT doc:

https://docs.microsoft.com/en-us/windows-hardware/drivers/display/tdr-registry-keys

To be fair, in reading it is an officially documented developer testing mechanism, not an officially documented end user workaround.

In fact they specifically advise against manipulating these values. 

Quote

 Important

These registry keys should not be manipulated by end users, or by applications outside of targeted testing or debugging during driver development.

Sort of a use at your own risk your mileage may vary registry setting that wasn't intended to be implemented by end users for long term usage.  Certainly not the first time we've  had to use those in FS though but I repeat my question, are LM's multi million dollar commercial customers sitting there tweaking their registry?  

The only thing I can think of is commercial customers aren't on 5.2 "or" we have a different 5.2 build because I can't see military customers around the globe accepting this for what they pay LM.  

 

[psolk 3,040]

9 minutes ago, SteveW said:

From my earlier post, no amount of trying Tdr settings in the registry fix this, also clearing out temp files and DX cache does not cure it. This happens every time the scenario window is shown. I can stop it by removing the "Sim" value in the default flight Prepar3D_Default.fxml:

        <Section Name="Sim.0">
            <Property Name="Sim" Value=" " />
            <Property Name="Descr" Value=" " />
        </Section>

P3D complains there is no default vehicle but the scenario screen completes without the hang. This is one of many possible problems that result in the hang. Not all hangs can be resolved with the Tdr entries in the registry.

The only way to stop the problem is to install an older Nvidia driver. I happened to have kept a few older versions, installing 451.67 stops this particular hang. In this instance it is on P3D v4.5 and 2080Ti.

Interesting, I am on an older driver version, will check which one b/c I've never seen this on 4.5  

Perhaps that is the answer altogether?  Revert to an older driver without the issue?  Especially if you aren't on a new 3K card the older drivers were designed specifically for our cards (2080ti in my case) anyway.

Edit:  456.71 here with no issues... 

Edited October 7, 2021 by psolk

[Ray Proudfoot 8,954]

I've just landed at EKCH after a perfect flight. Drivers are 471.96.

@psolk, I can understand your reluctance to get v5 but when it behaves it is better than v4. More fps for a given situation and the dynamic lighting is better. More work assigned to the GPU too to ease the CPU. I'm guessing LM and their military customers just use the supplied simple aircraft - not anything like the PMDG or FSL aircraft so in fairness to them if they can't replicate it it's hard to fix.

@RXP, as has been said that workaround by Microsoft is just for debugging and testing. Maybe that's what we're doing! 😁

The discussion in that linked topic contains bad advice such as using QWORD instead of DWORD. And the parameters to use are different. Given it happened in a different sim in VR mode in DX11 it's very different to our situation and shows it was happening in DX11 although I never had it.

@SteveW, if you can reproduce that with a default aircraft in default scenery LM will appreciate it I'm sure.

So with one successful flight behind me I'm not changing a thing now and let's see how things go. Another shorter flight after lunch.