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Unreal Engine is using 100% of my CPU


When I open the Unreal Engine Launcher it uses 30% of my CPU, and when I move the window around it goes up to 100%!!!

When I open the editor it gets much worse, the CPU stays almost at 100% of usage even though I'm at the lowest graphics quality

My computer specs are:

Toshiba Qosmio X70-A Intel Core i7-4700 MQ COU @2.40GHz 2.40GHz (8 cores)

32gb of RAM

Windows 8.1 64-bit

Intel HD Graphics 4600


UE4 is installed in the C drive which is a SSD

Zip files with Screenshots

thank you!

Product Version: Not Selected
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asked Oct 15 '14 at 04:18 AM in Using UE4

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avatar image Jonathan Dorman STAFF Oct 15 '14 at 03:01 PM

Hey alobf,

I'm investigating your issue. Can you send me your full dxdiag?

avatar image zhang.qiang Jul 12 '17 at 02:00 PM

hi i have the same issue on my computer! my computer specs are windows 7 64-bit Intel i5 2310 2.9G memory 8G ddr3 1333 nvidia gtx 460 1G

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Hi alobf,

We have not heard back from you in a few days, so we are marking this post as Resolved for tracking purposes. If you are still experiencing the issue you reported, please respond to this message with additional information and we will offer further assistance.

Thank you.

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answered Nov 04 '14 at 05:01 PM

avatar image demented_hedgehog Dec 07 '14 at 02:07 AM

This problem still exists.. there are duplicate reports of it: https://answers.unrealengine.com/questions/89958/will-the-high-cpu-in-unreal-be-fixed.html and https://answers.unrealengine.com/questions/72584/unnecessary-consumption-of-cpu.html and https://answers.unrealengine.com/questions/48621/411-cpus-annoyances-bugs-and-suggestions.html and I'm seeing it as well (fwiw). My machine is a linux box and I'm seeing this problem on version 4.6. (my machine is underspeced sp? with 4Gb of ram.. maybe it's thrashing? (I'm off to get some more ram now.. I'll let you know if it makes a difference)).

avatar image demented_hedgehog Dec 07 '14 at 03:54 AM

Still seeing the problem with more RAM.. uses 169% of my CPU doing nothing with a standard new project with starter content.. I've not touched it at all.

avatar image Jonathan Dorman STAFF Dec 15 '14 at 08:29 PM

Hey demented_hedgehog,

Sorry for the wait. I've been looking into this issue and here's what I've found: This is a Slate-related issue with Linux and while we're working on making Slate less CPU-intensive, it's a long-term plan. For the time being, you may need to use non-realtime viewports (clicking the Perspective button in the Viewport and setting it to one of the Orthographic viewports, for example).

avatar image demented_hedgehog Dec 07 '14 at 05:43 AM

Running the UE4Editor-Linux-Debug cmd I get a LOT of these

[2014.12.07-05.34.39:407][260]LogRHI:Warning: [API][Performance][Medium][131218] Program/shader state performance warning: Fragment Shader is going to be recompiled because the shader key based on GL state mismatches.

I also get all sorts of weird display artifacts. Using:

bolt:UnrealEngine$ lspci | grep VGA 01:00.0 VGA compatible controller: NVIDIA Corporation GK107 [GeForce GT 640] (rev a1)

With the latest NVIDIA-Linux-x86_64-343.22 proprietory graphics driver

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