CTD due to NVLDDMKM (at least %99 of the time) FIX!

I had constant random ctd nearly always due to NVLDDMKM. After much gnashing of the teeth, hair pulling and swearing at the pc i think i have fixed the problem. I have flown at least 5 different flight in different parts of the world for approx 2hrs each flight. NO CTD!
Al i did was go to REGEDIT
Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\GraphicsDrivers
created a DWORD (32bit) with the name TdrDelay and gave it a Decimal value of 50.

SO far so good! NO NVLDDMKM has stopped responding etc in Event Viewer/Administrative Events.

This is super interesting.

Every crash I have had in MSFS has happened after SU5, but all have been BSOD with that error or, less frequently, total freezes where the screen went black. I seem to have reduced the error frequency after updating drivers and reducing the max FPS from 60 to 39, but if it happens again, I’ll certainly try that tweak.

Thanks for sharing. :+1:

I reckon that means slow ram or bottlenecked data. Firewall or if not then your harddrive or possibly internet are too slow in engaging, it could also be a fragmented drive but then you could expect stutters. Mind you this is not a shoot em up game so it’s a good fix and something MS/Asobo should pay attention to.

I guess that could be the underlying reason for my crashes. I have an RTX 2070 mounted in a PC built in 2014 with an i7-4790K and similarly aged motherboard and memory. My SSD is SATA, but my internet is 300 mbit/s and very stable.

SU5 changed the load balance between CPU and GPU drastically, which might explain why I’ve only seen the crashes since then.

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Some background information on that option:

It would be good to know what is causing these timeouts in the first place, of course.

This won’t help anyone getting other types of errors, such as the dreaded 0xc0000005 CTD.

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Translation: Your sim has crashed for some unknown reason :crazy_face:

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The reason for the TdrDelay is that Windows doesn’t know if the GPU is working correctly or not. So it uses a timer figuring that the GPU is very fast processing everything a program sends it. If for some reason, the GPU doesn’t respond in a certain amount of time, Windows assumes the GPU is no longer working. Windows then tells the program (MSFS for us) that the GPU has died. Since MSFS needs a GPU, Windows stops MSFS from running which results in a CTD.

Changing the TdrDelay doesn’t “fix” any problems. If the GPU doesn’t respond for 60 seconds and then starts responding, the user (MSFS) is going to see a frozen screen for 60 seconds. Since there are many things MSFS is processing, a 60 second “pause” waiting for the GPU messes up the timing and synchronization of all the MSFS threads.

Other graphic intensive programs on my system have failed due to the nvlddmkm error so it isn’t a MSFS problem. AMD GPUs have a similar Windows timer problem. (The nvlddmkm error is NVIDIA GPUs only.)

It is possible to change the TdrDealy and other Tdr timer values by changing Registry values. It is even possible to turn the TdrDelay off completely. I’ve tried diferent TdrDelay values and have tried turning TdrDelay off. Nothing seems to “fix” the problem and mostly made the issue worse. I have reverted back to the default values. Different TdrDelay values may work for you depending on your hardware and GPU driver.

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Right… so where did you get this information from to do so? It might be good to provide people a lot more info in regards to what TD&R is before they go messing in their registry. Was your crashing with MSFS resulting in system freezes? Hardware stop errors through debugging can also be cause of faulty hardware as well, just a friendly FYI. As much as we would like to think our hardware doesn’t have an internal problem it may very well have.

Edit, cool I see a lot more informative responses have came.

An update…I had 1 ctd since first post…up the TdrDelay to 5000…and installed nVidia driver 461.72…That was 7 days ago…at least 20hrs flying…NO ctd as yet…

BTW…i have Windows 11 beta installed, i use REX Weather Force 2020, FS2Crew FBWA32NX and FS2CREW PBE, Navigraph charts and sometimes TrackIR v5…and my Community folder has 35gb of data in it…so if that isnt a cocktail for ctd i dont know what is! And so far not a single NVLDDMKM error…get a few DistributedCOM errors but thats to be expected…

I tried this fix last night and have not had a single CTD since the TdrDelay workaround. Usually it was every 3rd flight. Awesome! Thanks!

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Hey NyakaVT!
Happy that my suggestion has worked for you too! Great result! Did another two flights today(about 3 hrs) NO ctd, NO nvlddmkm in the Event Viewer/ Custom Views/Administrative Events…Did you revert to nVidia driver 461.72?
Very satisfying to finally get a complete flight with no ctd! Very, very frustrating otherwise.

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I’m using 472.12. I’ve done 19 flights since implementing the registry fix without any CTD, anywhere from 4 min to 54 min. Nothing really long, but before I would randomly crash even on short flights. Although I have been flying over areas with low AI traffic (Northern Canada), so if it’s ATC or traffic related there may still be crashes. I’ll update if they come back.

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Another update…another 20hrs flying with NO CTD…NO NVLDDMKM errors in Event viewer.

Ill take it as a positive that all is well NyakaVT as you havent reported any ctd!

I had these nvlddmkm crashes constantly in the past after I made some updates of bios and drivers on my 3080 and then tried to overclock. To prevent that I had to set my card in debug mode in the Nvidia Control Panel to get it stable.

I use an Aorus extreme 3080 with their bios which uplifts the power limit from 370w to 450w and I monitored, that these CTDs came when the card tried to take more power than 370w.

I had bad crashes in the past with an AMD card and what helped was flashing bios.

So it’s here, I flashed bios again and it seems to work stable now. My card sucks up to 420ish watts where it needs to, no nvlddmkm crashes anymore.

Good to hear you have no more nvlddmkm crashes with a different fix than mine, eklester! I had read that OC can be the cause of such errors but mine not because of that… Have a GeForce RTX 2080Ti factory oc and cpu is I9-9900 K , 3.60 Ghz base oc to 5Ghz(factory).

Did a 21hr(scheduled flight time) flight from YMHB to LFPG last night. Actual flight time was around 8 hrs. I sped the sim up between x2 and x4.
Used the freeware A330 NEO and it and FS2020 performed faultlessly. NO ctd, NO nvlddmkm. Im calling this done and dusted!