This has happened to me 4x in one day. I am floating around in my level not even moving anything around… just simple viewing it in editor as i move my perspective around… and thing not only freezes unreal, but it freezes my entire computer… i cant even control alt delete. It never returns… i am forced to push power button every time. What is happening?
I have attached my dx diag.
So far I opened this project up 7 times today… and all 7 times i froze my computer… sometimes within first 5 seconds of opening my level… sometimes its a few minutes of floating through air not grabbing any geometry in my level just scoping out how many draw calls in different areas.
I am not unfortunately stuck until there is a fix for this. I already spent like $10,000 on this project so to have to flat out stop in middle of development is killing me.
So far I am not sure how to replicate it… I will say latest thing i did was do a quick built on a work computer that i canceled because that computer would take forever. precomputed occlusion broke on me at that point so i went home and did a preview build … though i also did no precomputed occlusion on that build because i was just testing render times. Anyway… lighting is built and i float across level… and i freeze my computer randomly in this level. Its very reproduceable… sometimes u get lucky and u think all is well and ur floating around for 20 min with no problem… but mostly… this thing freezes up early on… ive crashed like 10x yesterday and once this morning and most of time it happens at start of level after walking forward a small distance… dont know if texture streaming is happening at that moment or what, but regaurdless it freezes my computer and only powering off machine with power button is my option. I dont want to destroy my computer by doing this over and over.
I cant recall if this froze before 4.9.1, but I will say occurence espeacially after last build has been happening like clockwork. Almost every time i try to do work on my map. Seems like 4.9.1 has broken everything from reflections view mode because u opened to project with VR at one point … to freezing me up completely…
I feel lost here… You cant really work on meeting deadlines when you cant do work at all period…
I can send you my project if need be to see if you could reproduce it. Its about 50 GB though 
Here is a screenshot i took with my phone of a free temperature software for my computers temps when computer crashed. You see i put editor in windowed mode and put this on other side of screen so i can see what it says when it freezes. And sure enough it froze first 5 seconds in my level and this is temps. I dont see any problems here temp wise.
Heres something funny. And i just noticed this. I made it crash again but… heres what i just noticed. When i unplugged my phone from frozen computer… I heard windows do its sound effect like something was unplugged. Then i noticed my mouse cursor still moves around… but everything with computer is frozen… i cant control alt delete… and only option is to hit power button… I have tried to leave it over night after freezing to see if it comes back… it does not. But its odd that hte mouse cursor still functions and i still get windows sounds from unplugging things.
Hi kurylo3d,
Looking at your dxdiag, your NVIDIA driver appears to be 355.84, when latest available on their site is 355.82. From your explanation, it sounds like your display driver is crashing or GPU is freezing in some way while PC continues running. Can you try downloading and re-installing 355.82 driver? It can be found here:
Also, let us know what anti-virus you’re using. Thanks!
This is latest VR driver… it is said to download that to use VR. I actually found link to that somewhere on unreal forums. It is on nvidias site somewhere.
Also I do not beleive I am using any antivirus software unless windows 8.1 has something that i am unaware of by default.
Heres a link. It was meant for latest occulus .7 which seems to work ok. Should i uninstall this driver and go back? Will this somehow screw up occulus .7?
Yes, please give older driver a try and see if it resolves this issue. If not, you can upgrade back to .84 and we’ll explore another option.
I’ve had this happen before.
What you’re describing sounds like it could be related to a corrupted asset consuming all of your physical memory. I’ve had issues with assets which I migrated from an older version of engine to a newer one, and during loading of an imported asset, asset loader gets an invalid memory size and tries to allocate something like 18 million bytes of memory. Obviously, computer can’t handle that but operating system tries anyways by freeing up that much memory by paging it out to your page file. This causes a complete system freeze which can only be fixed with a reboot.
What you should try to do is run engine with a completely blank project and try to recreate freezing issue. If you can’t cause your computer to freeze, it’s not a driver or engine issue. From there, it becomes an issue of trying to identify exactly which asset is causing freeze. That may be a pain in neck to identify, but it will take a lot of time and effort. My approach would be to import 50% of your assets from your game and see if any of those cause a freeze. If not, import 50% of remaining assets, and repeat until you get a freeze. If you use this halving method, you can identify asset pretty quickly.
Once you ID offending asset, you may have to recreate it from scratch.
I dont think thats issue. If my computer was unable to do anything then i wouldnt hear windows unplug sound instantly when i unpluged my phone… nor would i see mouse moving around flawlessly no jitter. Plus I so far have not been able to replicate this issue on anotehr computer yet. Also if it was a single asset… it should freeze every single time it pops up… so far this thing has frozen in all sorts of locations on map… not just same spot.
I will give that a try and let you know if I experience freeze again.
I don’t know about sound, but I was able to move my mouse without issue even though my computer was overloading memory. I could move mouse but not click on anything. You could keep task manager open and monitor your memory usage when you use editor. Look for massive spikes to 100% consumption.
Problem is task manger freezes up too… and it takes a few seconds to update. I somehow doubt my memory consumption goes from 3 gb to 16 gb in a split second.
Yeah, that’s exactly what I’d expect to happen if engine is trying to allocate a ridiculous amount of memory. computer will completely freeze all interfaces as it tries to allocate memory. memory allocation can happen in a split second and you may be lucky to see initial spike in memory usage as it goes up to 100% and beyond. After that, task manager will freeze as operating system blocks all other threads to handle impossible memory request. reason mouse would continue to work is because it is a hardware device which doesn’t get blocked by OS – I vaguely recall something about IRQs?
So… how do you identify this? In my experience, you can run engine from a source build and set solution configuration to a ‘debug’ build. engine will trap unhandled out of memory errors and you’ll be able to look through call stack to see what asset / part of game was causing an out of memory error. In my case, it was a corrupted asset which had an invalid file compression byte value at address 0xC (took a week to figure that out!)
No, it wouldn’t freeze your mouse (See: Interrupt Requests)
You can download source code for UE4 and run editor by building it. If there is something within editor which causes it to crash (such as an out of memory exception), program will stop running and show you where it encountered an error. This is better than having to forcibly power off your computer 
Also, you can figure out precisely which game asset caused error and that would let you go and ID and fix issue (if error is caused by your game and not engine).
If this sounds interesting to you, there are tutorials which will help you go through necessary steps to set this up.
Would it also not freeze mouse icon which changes based on if your in perspective view or anywhere else in windows… changing normally from whatever it hovers over ? Because my mouse changes icon depending what it is hovering over.
And I am an artist. Whta you just said about source build and debug build… all alien to me.
So far i have rolled back my graphics drivers and have not frozen yet. (fingers crossed)
If it crashes again I could give it a try, but fact that i could float around doing a loop around my level for 20 min…and have it not crash until 21 min… and then other times crash at 5 seconds going along same path… just doesnt seem like it would be even possible to look for a single asset by cutting things in half.
