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Have you experienced similar hub thermal issues?

  • Yes

    Votes: 3 60.0%
  • No

    Votes: 2 40.0%

  • Total voters


macrumors member
Original poster
Apr 19, 2017
Ukraine, Kharkiv city
I have recently purchased a Dynamode (8 in 1 hub) to use my quite old Samsung SymcMaster 21" external display. It is connected to my hub via DVI-HDMI cable. It has 2 types of SD cards, 3 USB 3.1, 1 Ethernet up to 1 Gbit, HDMI and USB-C power port.

As soon as I connect hub to MacBook the temperature of Thunderbolt die sensor rises from 35 to 50, if I connect my 1080p display it rises from 32C to 50-60C Celsius degrees on thunderbolt die (depending on what is connected to the hub). The hub metal enclosure itself also gets hot up to 40-45 degrees. But I am not so worried about my hub, I am worried about my MacBook. It’s cpu zone gets significantly hotter, CPU\GPU sensors show 60-68 degrees for CPU/GPU wile its use is within 10-18% stable.

Now I guess if it may be related to a specific hub, not pricey enough to be efficient or whatever else. It costed me 35 USD. A much bigger and almost with the same connectivity hub from Baseus (Enjoyment series, it is as twice as longer than mine and in general quite big) reaches 60 USD, but I am not sure if it help with the heat issue. What temperatures would be reached if it was a 4K display I guess now.

Has anyone experienced this kind of issues? My old MacBook Air mid 2012 operates the same display via thunderbolt 1 adapter and not even half hot as my new MacBook Pro 13 2019))) I’m kinda confused.



macrumors newbie
Aug 21, 2019
Gdańsk, Poland
Do u connect ur hub to left or right Thunderbolt? Apple recommends connecting to left tb ports.
I have found that that the left side ports seem more stable


macrumors G4
Jan 8, 2012
There isn't "cheap" Thunderbolt hubs, that is a USB-C hub. TB3 hubs are 10x that price and offer a lot more performance.

However what you are experiencing is normal. The Mac is now powering and controlling that hub. 5-10 watts is not abnormal merely plugging a hub in.

Here is my USB C hub (HooToo M# HT-UC008) I carry around which is has 2 x SD Card readers, 1 x 4k 30hz HDMI, 3 x USB 3 and 1 x gigabit ethernet.

Screen Shot 2019-09-06 at 5.12.02 PM.png

That is with NOTHING plugged into it, no HDMI, no USB, no ethernet, etc. Plugging accessories in can further increase the processing and power requirements and increase temps further.

If you are using all those USB-C hub ports then its required. I use a hub at work and home to connect external display, ethernet, and power via one cable. Plugging directly into the Mac via a thunderbolt 3 cable to HDMI (for example) is a more efficient way to connect because the Mac doesn't need to power external controllers.

CPU/GPU temps will rise due to the required additional processing via thunderbolt 3. Its hard to compare to your MacBook Air without knowing it was doing the same exact thing (1080p 30hz vs 1080p 60hz is effectively half the bandwidth).

4k will naturally have higher temps due to increased processing requirements on the CPU/GPU and higher bandwidth requirements through PCI > TB. 4k 30hz 8 bit I see 55-65c, 4k 60hz 10 bit (HDR range) I see 90c+.
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Peter Kämpf

macrumors newbie
Dec 13, 2019
Same here. A 16" MBP with an eternal USB-C hub (HDMI, RJ-45, USB 3.1, SD and micro SD card) gets too hot to touch even with a single USB stick plugged in. Same with an ethernet cable, nothing else. Both when plugged in on left and right side. That is ridiculous. Never mind the external power supply. On an accessory meant for a portable computer.
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