Instability and frequent crashing in 4.26.1

Hi All,

I am experiencing frequent crashing of late. It is particularly bad when opening the MetaHuman project - but not exclusively. I’ve noticed a few consistencies prior to UE4 bailing out;

1.Almost every time I select a drop-down menu, that specific component of the GUI flickers then crashes.

2.If I use the scroll wheel on my mouse, it also tends to fall over.

I appreciate the MetaHumans project is quite demanding, but my PC is relatively new and reasonably powerful. I use a lot of DCC applications for VFX and UE4 is the only one I’m having issues with. I routinely handle volumetric lighting, particle effects, fluid sims, RBD’s - you name it! Only UE4 is giving me problems. I have a 16-Core AMD Ryzen 9 3950X CPU, 64 GB of RAM and an NVIDIA RTX 3090.

I know other people with similar setups who aren’t experiencing the same issues as I am. I’m hoping someone can shed some light on this; as currently UE4 is completely unreliable for me. I’m used to working in a production environment, where the software is mostly reliable - even in demanding circumstances. I really want to resolve this and actually begin to get the most out of this fantastic engine.

Thanks in advance,

D

Can anyone shine a light on this please?! Since I posted the initial query I’ve tried a few more things;

a)I’ve performed a completely fresh install of both Unreal Engine and the Epic Launcher.

b)I ran some A/B comparisons yesterday with an old workstation.

The old workstation spec is as follows;
NVIDIA K5200 Quadro
Intel Xeon E5-2630 v3 2.4GHz 8-Core
32GB RAM

I basically opened and ran all the projects and levels that had crashed on my current machine. Although this box is significantly slower than my new one, I ran it all day and it didn’t fall over once! While I’m fully aware a Xeon CPU and Quadro GPU are workhorses that would be expected to be more stable, my newer setup of Ryzen 9 3950X CPU, 64GB of RAM and an NVIDIA RTX 3090 should be more than capable of dealing with Unreal. I also spoke with the hardware provider and they ran some tests remotely, but could find nothing wrong.

I’m wondering if there’s a simple conflict somewhere between Unreal and the hardware, because my current box shouldn’t even break a sweat with the projects I’m running. Does anyone have any suggestions on this? Or even someone who has a similar spec machine with the same components? Maybe you could share some insight on what settings, drivers and configuration you are using?

I can supply 4-5 crash logs if it helps, but I really would appreciate a qualified opinion on this; as I’m running out of ideas fast!

Thanks,

D

Here are a selection of crash logs - I’ve named them after the task I was performing at the time of the crash.


330322-

I run a Ryzen 3900X with 32GB RAM and a 3080 and have the same issues. I can just have a project open and if I click or hover over anything it freezes with a crash following. It’s completely random too. Sometimes I can work on the project for hours with no crash and other times it crashes as soon as I open it.
Never had them in 4.25.

Looking at the stack it seems to be crashing from Render Hardware Interface → Direct X → NVidia drivers.
1: Try updating (or downgrading? Saw a post before that Nvidia 461 drivers have issues with UE but 460 don’t) your Nvidia drivers.
2: Try switching the editor to DirectX 11.

Thanks for sharing your experience on this. It’s interesting to FINALLY hear of someone with similar instability - on pretty comparitive hardware. I wish - at a bare minimum, there was at least more documentaion on compatibility/confifuration specs for UE releases with commonplace hardware.

I definitely have more luck with 4.25, but on my new box none of the last four releases perform as reliably as they do on my old Precision workstation - which has only around a quarter of the computational grunt - it doesn’t make sense! Obviously, I expect the odd crash, but my old box is rock solid by comparison.

Sadly, I’m not seeing any evidence of Epic responding on here and don’t know of any other way to make contact to obtain an authoritative answer. It’s very frustrating.

Thanks for these tips! I have rolled back the nvidia driver to the previous studio driver 460.89. Nvidia’s own release notes for it specifically suggest it has been optimised to perform well with UE4.26.1 - so fingers crossed on that. I have one quick question for you though. How exactly do you switch the editor to DirectX 11? Looking at the projects settings, it looks as though you have to have 11 and 12 active simultaneously - please see attached? Thanks in advance.

You’ll want to change the Default RHI, like so:

330834-directx.jpg

You Sir, are a lifesaver!

I have rolled back my GPU driver to the previous Studio version - 460.89. Nvidia’s release notes for this particular driver, highlight the fact it has been optimised for Unreal Engine 4.26.1 - the version I’ve been struggling with most. I also switched from DirectX 12 to 11 - found it under the Windows section thanks. I’m not certain if there’s any benefit yet, but so far, so good.

I threw a fair amount at the workstation yesterday afternoon and have witnessed a significant improvement in stability. In fact, I’ve only seen two crashes in 4-5 hours - which was on a demanding project with RT ray-tracing enabled. Previously, I would have seen 20-25 crashes during a similar period.

I have one final question for you. I also tested the MetaHuman sample project last night - which always fell over previously. Again, since implementing your suggestions it was vastly improved. The one thing that pushed it too far was trying to run the cinematic from the sequencer - please see attached crash log. Tried this twice and it crashed at the same point with the same CL. Any idea what this means - this looks like a very different set of complaints to before?

Thanks again for all your advice,

D

Not certain if you’ve seen this? But take a look above and see a couple of straightforward adjustments that were suggested. They’re definitely worth trying, because so far it has worked well for me. Basically, rolling back my GPU Studio driver from 461 to 460 and switching DirectX 11 - from 12 in UE4.

Good luck!

Yeah now we’re crashing in Unreal’s code. You should definitely press one of the “Send and […]” buttons to send that crash report to Epic.

I can only see which modules are crashing from the stack, if you download the editor symbols (from Epic Launcher → Unreal Engine → Library → Small “Down” arrow on your installed UE button → Options → Enable Editor Symbols for Debugging (around 30 GB) → Apply) then we can see which code lines are actually failing.

I don’t know if I can help with that, probably more for Epic Staff, but it might give better hints to how to get around it.

Seems like a MovieScene is interacting with a ControlRig which has an invalid Quaternion (Rotator). It’s expecting a normalized Rotator but didn’t get one.

Sad thing is that I can’t roll my drivers back because I need newer drivers for DLSS and switching to DX11 is a no go because it’s a full RT project. So while those might be workarounds of the issue it doesn’t FIX the issue and a fix is a must because you can’t ship a product with workarounds.

Good to know. Again, thanks again for all your input - it has been genuinely invaluable.

Have a good one!

D

Sorry to hear that, I can see how frustrating that must be. Hopefully there will be a patch soon that resolves these issues - although UE5 can’t be far off now?

I have the same problem yet!! what should I do?

I’m also experiencing this problem. - i7 5960x & RTX 3090.

The Metahuman sample project is visually glitched when i open it - the interface as well, and when i move the mouse it gets worse, with black screen, and quickly crashes.

I was on the latest updated Studio Driver, tried rolling back to the Studio version 460.89 but the same thing happens. I can’t even try to switch to Directx 11 because of the glitches, Unreal is unreadable, and crashes before i can do anything.

The other projects i have opens without a problem.

Anybody solved this issue ?

Here’s a screenshot of the glitched interface…

I had a half a year marathon of 5 - 100 crashes a day with this processor. I tried everything, including reinstalling to a different OS and changing GPU.

I just changed the motherboard and processor to Intel, and, knock-on-wood, I did not have any crash in the last 6 hours.

Here is my thread, and things I tried before switching to Intel: