whenever i try to use unreal engine, my pc fans go nuts because it’s trying to use my cpu for everything instead of using my gpu at all, and it’s not like have a bad pc either, i think it’s just trying to use my integrated graphics or something instead of my actual gpu, is there a way to make it use my gpu instead?
whenever i try to use unreal engine, my pc fans go nuts because it’s trying to use my cpu for everything instead of using my gpu at all,
Luckily that’s not how things work.
It would be impossible for the engine to use CPU in place of the GPU or vice versa (unless you rewrote the rendering pipeline) and did not pull off some other crazy engineering. There are certain engine features that may require one or the other, ofc - like particles:
One of the particle types available in Unreal Engine 4 is GPU Sprites . These are particles that are first spawned on the CPU, but then processed and calculated entirely by the graphics card. The benefit to this[…]
Rather than trying to eyeball what is going, why not run monitoring software that will tell you precisely what is being taxed. Something as simple as GPU-Z can monitor multiple GPUs. Even the humble Task Manager under Win10 can do both.
it’s not like have a bad pc either
This usually means a somewhat modern Windows Desktop machine, but who knows - perhaps you can tell what OS and hardware we’re dealing with.
Do note that a GPU under load would, generally, output more heat than a CPU (on average - just look at the Wattage); your PC (a laptop perhaps?) could be in real trouble while both are utilised to their full potential. There is a reason why frame limiters are a thing.
You did not specify whether it’s a laptop or not, but with the former, the same cooling components are often responsible for removing the excess heat for both the CPU and the GPU, at least in more beefy models. It would not matter what is heating up, it needs to be removed anyway - so you pipe it (literally) to the heat exchange.
Now, discrete GPU vs integrated GPU vs an APU is a different story. While this should no longer be an issue (it used to be in the early days of UE4), it’s not entirely impossible, ofc.
Can you confirm that you actually observe this very incorrect behaviour? Also,
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yesterday i was doing a ue5 tutorial and i was doing a light build thing and my cpu went up to 100% while my gpu wasn’t really doing much, it made my cpu go up to 94 degrees celsius and i don’t want that to happen every time ue5 tries to do something intensive
also it’s a pc not a laptop, i have a 3060 and an intel 17-10700k
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Perfectly normal. This is a CPU-only process.
it made my cpu go up to 94 degrees celsius
In short - the CPU cooling is inadequate here.
The tJunction temp for the i7-10700k is 100C. This generally means that you must do everything you can to keep it under 90C if you want preserve longevity. It may be fine to spike to 100C every now and then but keeping it there will shorten the lifespan of that chip. Above 100C it will throttle and this is a critical, very unsafe point.
You want a cooling solution that will keep that CPU at 80C at 100% utilisation for hours and in the middle of the summer heat to boot. Not the easiest task but a bigger, meaner fan will do the job.
Before you splash out:
- clean the fins on the radiator
- get rid of the dust and dust bunnies
- ensure the air is moving unobstructed and in the right direction, pulled from one side and pushed to the other
- ensure the fans that are supposed spin do so
- crank up the case fans if possible
- are we sure the thermal paste is doing its job?
If you’re using liquid cooling, this temp is not acceptable at all.
Imagine what would happen inside the case if both the CPU and GPU were under 100% load for a prolonged time.
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so there’s no problems with how ue5 is running? i just need to deal with the heating problem?
Does you CPU go to 100% when you do not build lightmass and use the engine for something else? 10700k is a very capable chip.
Even so, the processor and its cooling should be able to handle 100% load for 24h without overheating. Games are generally not that demanding, but the tools used to make those will take everything you throw at them, be slow and ask for more resources.
What cooler is on the CPU? Perhaps it’s a matter of cleaning it.
If your CPU has integrated Intel graphics then it very likely could be using that instead of your more powerful Nvidia GPU. To fix it you go into the Nvidia Control Panel an in the 3D settings set the Nvidia GPU as the global default
no it only went to 100 when doing the light build thing, i’m just afraid of it overheating if it needs to do something really intensive like that again, i didn’t know it was a cpu only thing
also i have the Cooler Master Hyper 212 EVO 82.9 CFM Sleeve Bearing CPU Cooler
which option exactly in the 3d settings should i be changing?
Under “Manage 3D Settings” there’s a drop down box that by default would be set to Auto-Select, change that to High Performance NVidia Processor
And how does it help with CPU overheating?! It’s exceptionally unlikely that your PC is using the wrong GPU, you’d be running the engine so slow… Anyway, just check in the Task Manager which GPU is being taxed, it’s 3 keys away… Shift+Ctrl+Esc
i’m assuming that’s the opengl rendering gpu setting then cause that’s the only option that has that
idk why it gets so hot lol
No, it’s a global setting that has nothing to do with OpenGL/DirectX
By default, Windows will try to automatically choose which GPU to use if you have more than one, the most common example is a laptop like yours with an Intel processor that has an integrated GPU along with a dedicated Nvidia GPU. It does a poor job of managing it so you should get better performance by setting it to only use the Nvidia GPU. The battery will drain faster, but it’s necessary for the best performance.
It’s not a laptop, and OP has not complained about performance. He wouldn’t be able to use UE5 on the integrated HD 630 anyway - not without a choppy 5-10 fps in the viewport… And OP can check what the HDMI is connected to. Although I’ve seen desktops having the HDMI plugged into the wrong port - but that’s extreme malpractice 
And even so, if your CPU at 100% + iGPU under load are hitting 95C, you have a cooling problem anyway. Use any other app that pushes the CPU, you’ll get identical results. Prime95 it and you’ll hit 100C in 5mins.
Nothing to do with the editor unless you’re observing very high utilisation non-stop without it performing any tasks.
Why not open the Task Manager and observe which GPU is being used - takes 5 seconds…
My secondary rig has 2 GPUs + iGPU.
Cooler Master Hyper 212 EVO
It’s a decent cooler. It’s either not spinning fast enough, the thermal paste was not applied correctly / has dried out too much (unlikely, but who knows), it’s a tiny case with no air flow, you live in 40C heat or all of the above.
IMHO, it’s a cookie-cutter cooling issue.
if the setting is there then i can’t find it, i don’t know which one it is
maybe i’ll just try and cool my cpu better then by getting another fan or something, thank you for the help
also i know this doesn’t relate literally at all but i wanna ask anyways, whenever i’m clicked on unreal engine my gpu usage goes WAY up due to for some reason desktop window manager using a ton of it and i have absolutely no idea why, is that normal?
Since your GPU is not doing much, you can use its fans while your CPU is cooking something, you can override what the GPU fans are doing with afterburner 
for the duration of the cook:
But seriously, just ensuring the case is well ventilated and not sucking hot air from the room radiator is a good start. You could underclock the CPU but you generally do not want it to go slower. People do all kind of strange things to keep temps in check.
whenever i’m clicked on unreal engine my gpu usage goes WAY up due to for some reason desktop window manager using a ton of it and i have absolutely no idea why, is that normal?
If it’s a spike and then it goes away, it’s normal. Is it the 3060 that you see being used in the Task Manager?
Do note that the editor is using the GPU all the time, it’s just does not need a lot when you connect wires together. If you were to work with graphically intensive stuff, it will be underload all the time.
it is the 3060 yes
maybe i’m just being paranoid cause usually i am when i see it use a lot of my hardware lol
i’m assuming i probably just need to fix the cooling problem then
I’d say that’s a good thing, you paid for the entire PC, use the entire PC! Do stay vigilant of course, in the olden days there were dozens of threads like this:
Never experienced it myself, but too many folks reported the launcher using 70%+ CPU time consistently for it to be just a fluke. That should not be happening and is no longer a thing (that anyone talks about, at least).