# CPU Overheating when building light **URL:** \ **Category:** Rendering\ **Tags:** unreal-engine, CPU, Level-Design, question\ **Created:** [February 1, 2015, 5:02am UTC](https://forums.unrealengine.com/t/cpu-overheating-when-building-light/305617 "2015-02-01T05:02:46Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![The\_Shane](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@The\_Shane](https://forums.unrealengine.com/u/The_Shane)\ **Post date:** [February 1, 2015, 5:02am UTC](https://forums.unrealengine.com/t/cpu-overheating-when-building-light/305617/1 "2015-02-01T05:02:46Z")
As the title says, my CPU temperatures are breaking 100_C (at about 85% capacity) when trying to build light for a level that’s only got 440 actors in it, almost all of which are just brick walls from Manufactura K4’s Ancient Environment kit. I believe I have ~10 lights placed throughout so far, all of which are shadowless. It rests at about 80_C and 120 FPS while navigating the viewport. Is my level too big? I’d like to hope my computer could handle what’s only about half of the skeleton of the dungeon, but I’m not sure what else I could be doing. Here are my specs - i5-4670k CPU @ 3.40 GHz - GeForce GTX 760 - ASRock Fatal1ty Z87 Killer Motherboard - Windows 7 64-bit - 8 GB RAM It’s worth noting I only have the default CPU cooler installed as the EVO 212 I ordered doesn’t fit in my current case. EDIT: I popped off the side of the case tonight while attempting to build the lighting and managed to do it without breaking 100\*C. I was watching my CPU and it never broke 80%, so it must just be something with my CPU cooler. ---
**Author:** ![Shadowriver](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Shadowriver](https://forums.unrealengine.com/u/Shadowriver)\ **Post date:** [February 1, 2015, 6:44am UTC](https://forums.unrealengine.com/t/cpu-overheating-when-building-light/305617/2 "2015-02-01T06:44:07Z")
If your computer cant handle CPUs on full usage it means something wrong with your cooling system or it simply sux (but default should really handle it if you mot overclocking), its not really UE4 problem ---
**Author:** ![The\_Shane](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@The\_Shane](https://forums.unrealengine.com/u/The_Shane)\ **Post date:** [February 1, 2015, 7:56am UTC](https://forums.unrealengine.com/t/cpu-overheating-when-building-light/305617/3 "2015-02-01T07:56:51Z")
UE4 is the only thing that brings it even remotely close to these levels, which is why I’m asking about it here. I wasn’t sure if there were others with similar specs who could tell me how their UE4 experiences have compared. ---
**Author:** ![Ben85](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Ben85](https://forums.unrealengine.com/u/Ben85)\ **Post date:** [February 2, 2015, 8:03am UTC](https://forums.unrealengine.com/t/cpu-overheating-when-building-light/305617/4 "2015-02-02T08:03:59Z")
Although the thermal performance of the standard Intel heat-sink is quite poor, it’s not _that_ bad at standard frequencies. I imagine if you run Intel Burn Test (or any other application that maximises CPU utilisation), the outcome will be the same. You may need to replace the thermal paste and reseat the heat-sink. ---
**Author:** ![anonymous\_user\_3221808d](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_3221808d](https://forums.unrealengine.com/u/anonymous_user_3221808d)\ **Post date:** [February 3, 2015, 6:34am UTC](https://forums.unrealengine.com/t/cpu-overheating-when-building-light/305617/5 "2015-02-03T06:34:10Z")
It does seem you have an issue but you should be able to reduce the local processor count in swarm to reduce the usage. ---
**Author:** ![Arty-McLabin](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/arty-mclabin/32/1012076_2.png) [@Arty-McLabin](https://forums.unrealengine.com/u/Arty-McLabin)\ **Post date:** [January 30, 2018, 12:03am UTC](https://forums.unrealengine.com/t/cpu-overheating-when-building-light/305617/6 "2018-01-30T00:03:52Z")
sorry for necro, can you xplane how to do that? thanks :] ---
**Author:** ![pronacx](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@pronacx](https://forums.unrealengine.com/u/pronacx)\ **Post date:** [June 8, 2021, 2:11pm UTC](https://forums.unrealengine.com/t/cpu-overheating-when-building-light/305617/7 "2021-06-08T14:11:43Z")
get a water cooler i personally use deep cool and its stays around 50 degree on 100% load i downclocked my cpu but it works fine