# Macbook Pro fan runs very loud even when doing nothing.



## BrooklynAngel (Dec 24, 2020)

Hi, I have a new macbook pro, and I upgraded to the new OBS 26.1 to run a test stream and noticed that fans ran so high even after only 2 minutes. So I downgraded back to OBS 26.0.2. Did another test stream and encountered the same issues. I haven't upgraded to Big Sur yet, I'm using Catalina 10.15.7.

I have a 
MacBook Pro (16-inch, 2019) 
Processor 2.4 GHz 8-Core Intel Core i9 
Memory 64 GB 2667 MHz DDR4 
Graphics AMD Radeon Pro 5500M 4 GB 
Intel UHD Graphics 630 1536 MB 

So it's definitely a high spec mac. 
Not sure why the fans are running so high and loud. Especially after only 2 minutes. Checked activity monitor which was at 150% CPU for most of the test stream, when I tried playing a video or display capture and even tested windows capture, it spiked up to 210% CPU.
The fan is too loud to work with.


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## thomaslfessler (Dec 24, 2020)

What's going on with GPU utilization?   Command-4 in Activity Monitor.   OBS performance seems to be directly tied to the size of the Rendered Image that's displayed on the screen.     The fans also cool the GPU and if it's being excessively used, it's going to quickly heat up in the cramped MacBook Pro case.   

This post on the OBS Mac Forum has more info on the subject and how to reduce GPU usage:  https://obsproject.com/forum/thread...-excessive-gpu-utilization.136030/post-499658


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## BrooklynAngel (Dec 25, 2020)

So how would I stop the fans from going crazy?


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## thomaslfessler (Dec 25, 2020)

BrooklynAngel said:


> So how would I stop the fans from going crazy?



Hmmm - some thoughts..

Open Activity Monitor Press Commnd-1 and Command-4.
Look at what's chewing up all of your CPU cores.   200% CPU utilization is nothing with the processor you have. 
Disable HiDPI resolution on the display you are using and see if that helps to reduce GPU utilization.
Make sure you are not running any other apps in the background.
Grab an app like MacsFanControl and increase the baseline fan speeds on you Macbook Pro to a tollerable range, that prevents the CPU/GPU temps from getting TOO hot and going into Full-Blast mode


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## BrooklynAngel (Dec 25, 2020)

3 minutes in, no apps running in the background. Only 2 chrome windows open. Fans going at full blast.


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## BrooklynAngel (Dec 25, 2020)

I have no idea how to Disable HiDPI resolution. I went into display settings and don't see anything that allows me to do that.


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## Frag Tagger (Jan 12, 2021)

Just got OBS and it was a saviour as it can do something Ecamm can't: rotate the video streams. .... but my 2019 MacBook pro on Big Sur is doing this same thing - crazy fans. Is there no fix to this yet?


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## Frag Tagger (Jan 12, 2021)

Just found the problem - all 2019 16 inch MacBook pros have screaming full fans when connected to an external display. Grr. I have implemented all 3 "fixes" here, and it's better.. but not silent. I currently have Brave, OBS, and Mail open and the fans are running at 4100 rpm - would be a lot more if I did not implement these settings.   I'm really disappointed by this 16 inch MacBook pro.


			https://www.youtube.com/watch?v=EkmdHVfk4XE&list=PLCRPsbW_rIwLu6m2TDxVg5255Qdyrb4AT&index=5&t=3s


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## ShadowBark (Jan 14, 2021)

I have basically the same machine. I have a MBP 16in 2019, i9-9900, 64GB RAM, and 5600M. I also have it connected to an external display. When running to the display, it does not always blast the fans at full speed (being an audio / voice recorder, I would not be too happy with that). However when using OBS Studio, it does ramp up the fans. The only fix I could think of was getting a custom fan controller for Mac. I use it to lower the fans just while I do my audio recordings. However with that being said, I don't recommend this for long term. With how nice your machine is, I would hate for it to burn out quickly due to overheating. Monitor your temps, and adjust fans accordingly. The i9 runs pretty hot, so it's hard finding a sweet spot. Getting a temperature monitor as well as a fan controller would be your best bet for short term recordings. For long term streams and recordings, I'm not sure how to help.


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## huedoku (Mar 4, 2021)

Frag Tagger said:


> Just found the problem - all 2019 16 inch MacBook pros have screaming full fans when connected to an external display. Grr. I have implemented all 3 "fixes" here, and it's better.. but not silent. I currently have Brave, OBS, and Mail open and the fans are running at 4100 rpm - would be a lot more if I did not implement these settings.   I'm really disappointed by this 16 inch MacBook pro.
> 
> 
> https://www.youtube.com/watch?v=EkmdHVfk4XE&list=PLCRPsbW_rIwLu6m2TDxVg5255Qdyrb4AT&index=5&t=3s


 
I am disappointed as well. I feel like I spent $3000 and my old air ran faster. BTW, sorry if this is a repeat comment but use the right side USB C port for power. (It doesn't solve the external monitor problem but it does help generally overheat less) - I finally disconnected my second monitor and am using an old computer to see my output.. lame


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## JohnBBeta (Mar 5, 2021)

same here - but it works. june 2020 maxed out 13" MBP. fans on full the whole time I'm streaming. no external displays connected - but a lot of stuff going on on my OBS set up. these MBPS just seem to run really hot - i remember linus tech tips flagging it on launch - not a lot we can do IMHO - apart from wait for proper M1 support...


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