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ressac

macrumors regular
Original poster
Oct 30, 2011
110
10
usually i don't use my mac with external screen, only for watching movies(720,1080) with vlc, streams(720p) with chrome or safari (youtube ....)

i'm using official apple adapter usb-c to hdmi with 1080 screen
so after about 5 mins fans starts to increase from 2000 to 2500 even if it idle and then about 5min more they getting 3000-3500 in case if im watching something

if mac is idle, fans stays on 2500

i know that if external screen is connected macos using gpu(not intel hd) by default

so i really confused about it, because keyboard and palm rest also gets WARM and it doesn't feel comfortable, i didn't expected this from new mbp 15" models

so, if it's happens only to me? more ppl who experiencing this kind of problem?

i attached two screenshots, you can see that after connecting external screen more power is used even if it's idle, because gpu is used
 

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When you say it's a problem, is the computer crashing, experiencing shutdowns etc? Saying it gets 'warm' is not a problem in of itself, it's normal use for an electrical device to generate heat when drawing more wattage.

And looking at those screenshots, you're increasing the temperature by about 5'c, whilst drawing about 8w more power. Which adds up perfectly fine, the GPU is being used to provide the extra display, and is running about 2-3'c warmer than in idle. Fan wise again totally normal, things generate more heat and the fans increase to offset this and attempt to cool it down.

Best advice is to uninstall all these temperature/fan monitoring tools and just use the computer without worry, trust that Apple have spent millions making sure the thing won't melt, and if it does suddenly melt through the desk then take it to an Apple Store and have a chat about it.
 
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As New Mac Smell says nothing here is abnormal, using an external screen uses the GPU because the video output is connected through the dGPU in the 15 inch machines.
This will use more power and generate a little heat, very little according to your screenshots.
Your mac is rated to shut down when the CPU/GPU reach 105 degrees centigrade to protect your computer but running at full tilt it will run for hours at 95-100 with no real adverse effects its a computer it generates heat and has cooling systems and fail-safes built in to protect it.
Due to the metal chassis this acts as a heat sink but does also make the surface warm to the touch sometimes its a trade off for chassis materials, as long as its not uncomfortable I don't see an issue. If its not what you want buy a plastic laptop that simple really.
 
well okt then, but i really don't find it comfortable using warm keyboard while i don't do hard tasks on machine, also I had noticed more people wrote before me about this issue in this forum.
 
well okt then, but i really don't find it comfortable using warm keyboard while i don't do hard tasks on machine, also I had noticed more people wrote before me about this issue in this forum.

You get the question posed about once a week here, I see you've used the search feature so the answers should largely be within them. Short answer is people are overly concerned about heat and become obsessive with various fan control apps and stuff, you really should just leave this stuff to the system. Not to say you are obsessive or anything, just a general comment on the number of threads.

It shouldn't be so warm that it's uncomfortable, but because of physics it will get a little warm to the touch. If it's scorching hot alla car steering wheel in summer then it would be an issue. From your use it's running perfectly fine, you'll always get heat with a laptop and a little more with a metal laptop as @Samuelsan2001 pointed out, but there's not really anything that can be done about it.
 
i agree with you, but i had used previously two mbp 13" with external screen, none of them had warm keyboard as 15" 2016 and i think it's because of amd chip, that why i decided to ask.

anyway thx everybody, i think we can close this thread as no questions left.
 
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