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(2019) 16" is HOT & NOISY with an external monitor! :(
- Thread starter Appledoesnotlisten
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My 2014 is attached to a 4K monitor and running my trading software. The bottom is warm but it's not hot. I can't hear the fans if they are running. My 2015 is attached to 2 QHD monitors and the bottom of the laptop is just slightly warm - certainly not as warm as the 2014. But it's not running my trading software either. It's running my office workload which is lighter than my 2014 is running.
It may be that Apple may need to do some OS tuning with the new GPUs.
It may be that Apple may need to do some OS tuning with the new GPUs.
In an earlier post, I tried to explain to the OP that running the displays using ANY kind of "scaling" was going to make the laptop work much harder, but I don't think that it "registered" with him...
That does not help though, as using some external screens unscaled is not really an option.
Does the "More Space" option in far right affect how the GPU works?
It looks the original resolution to me. The "default to display" looks like a scaled UI. Am I correct?
Just commenting on the two attached screenshots:
It seems you are using SwitchResX
3840x2160 HiDPI on SwitchResX means 7680x4320 at 2x Retina, for a 4K display you should use 1920x1080 HiDPI which is effectively 3840x2160 (which would explain the 30hz).
Thats not a problem for machines like 13” touchbar, you’d not run 5k native.
Newer MacBook Pros use a scaled resolution as their "standard" resolution in the settings.
Unscaled means native resolution or half of that. That is when the GPU has to do the least work. For the old 15" that would be either 2880x1800 or 1440x900.
I just got mine yesterday. i7/32GB RAM/512GB SSD/5300M. I was a bit worried about this as I'm basically using the MBP as a desktop replacement, but mine is very quiet.
In clamshell mode it runs even quieter, for daily tasks I don't hear the fan spin up at all. With the lid open the fan is audible, but it's just a low pitch noise, not annoying at all.
I'm driving a 3440x1440 display (34GK950F) with it, so no scaling is going on which may be a factor. However, it's also a 120Hz display which certainly adds a lot more demand on the GPU. My old Surface Book couldn't drive this monitor at its native refresh rate without dropping frames frequently.
In clamshell mode it runs even quieter, for daily tasks I don't hear the fan spin up at all. With the lid open the fan is audible, but it's just a low pitch noise, not annoying at all.
I'm driving a 3440x1440 display (34GK950F) with it, so no scaling is going on which may be a factor. However, it's also a 120Hz display which certainly adds a lot more demand on the GPU. My old Surface Book couldn't drive this monitor at its native refresh rate without dropping frames frequently.
Have you tried running any VMs out of interest, or full screen 4K video even - does the fan behave itself ?
I’ve left my 2019 15” base connected to a 5K LG since I got it and it’s never got noticeably hot or noisy unless I was doing anything intensive and/or the ambient temp was too high or poor ventilation.
Something definitely looks off there. The fans being nosier in general isn’t a surprise since they’re bigger in the 16” but it shouldn’t be running that hot just idling.
Something definitely looks off there. The fans being nosier in general isn’t a surprise since they’re bigger in the 16” but it shouldn’t be running that hot just idling.
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This is really encouraging to hear. I'm runnning the same config of a 34 inch 120hz ultrawide and have the same results for noise level. You can set you monitor to 60hz though if you want to strain your system less btw.
When playing 4K video it is nearly silent. In VLC, I only see like 15-20% CPU usage.
Haven't tried running any VMs yet, right now I run those remotely on a server. I tend to have a ton of stuff open in Chrome, usually around 30 tabs, so it's impressive the fan is not kicking up. In VS code I have a language server running for PHP as well which can use quite a bit of CPU when it is indexing, but that hasn't made the fans loud either.
No such thing as a free lunch. The GPU has to work hard doing a lot of scaling and it is going generate a lot of heat. In a small MBP case the fans have to spin up to dissipate the heat. The same work in a deskside tower generates the same heat, but the dedicated GPU heat sink is the width of a macBook pro and an inch thick, and has 3 fans dedicated only to cooling the GPU heat sink. No surprise that this GPU is very cool and fans run at low rpm and are quiet.
Laptops always have compromises driven by the portability requirement.
I have my 16" hooked to the LG 5K Ultrafine monitor, and I'm not seeing any fan or excessive heat. The area just above the Touch Bar is warm/borderline-hot, but actually less so than my 2016 15" MBP was.
I'm scratching my head reading the OP, because my new 16" with 5500/8GB is literally silent while sitting here in a browser attached to my 1440 ultra wide (not quite 4k amount of pixels, but close).
The fans will spin up a bit when I'm building with docker-compose and when I slap my local development database around, but for general web/email/chat/music my machine is silent and cool so far. I guess I'm comparing it to fan RPM/Loudness of my 2012 original Retina MBP, but under the same workflow I'm actually impressed at how much less heat/fan noise I'm experiencing.
In bootcamp, playing games, it's definitely working hard and making noise... but judging by the performance it seems to keep the machine cool enough to run at a reasonably stable CPU/GPU temp and speed.
I'm also experiencing this.
Just doing email and web browsing when in dual display mode, (MBP 16" + 4k Samsung), will make the fans go to 4000 RPM minimum. (Scaled/no scaled modes doesn't change the behaviour at all).
If I close the lid and use a single display, it behaves and goes back to basically silent.
Seems like once the dGPU switches on to drive two displays, it gets very hot. The CPU is doing nothing. Would hate to see this thing driving 2x 6k XDR displays.
EDIT:
As soon as I shut the screen on the MacBook and just use the external. Fans are silent.
Or vice versa if I unplug the external monitor and just use the MacBook Pro screen.
Just doing email and web browsing when in dual display mode, (MBP 16" + 4k Samsung), will make the fans go to 4000 RPM minimum. (Scaled/no scaled modes doesn't change the behaviour at all).
If I close the lid and use a single display, it behaves and goes back to basically silent.
Seems like once the dGPU switches on to drive two displays, it gets very hot. The CPU is doing nothing. Would hate to see this thing driving 2x 6k XDR displays.
EDIT:
As soon as I shut the screen on the MacBook and just use the external. Fans are silent.
Or vice versa if I unplug the external monitor and just use the MacBook Pro screen.
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Hmm, the MBP only sees it as 120Hz? Guess it’s still limited to DisplayPort 1.2. Thats a shame.
But yeah. Using native resolutions is less taxing on the GPU. 120Hz isn’t too bad, really. Scrolling and moving windows doesn’t stress the CPU that much more, but the GPU does work a little harder to raster everything. But it’s not the same as gaming at 120Hz.
I have the monitor in DP 1.2 mode since I'm connecting through a KVM switch (unfortunately, there are still no DP 1.4 KVM switches that I know of). So that limits it to 120 Hz.
However I did just try connecting to the monitor directly and put it in DP 1.4 mode, that made the 144 Hz selectable and it works fine.
I did some testing when I got my 2017 15", and found out that most of the heat is caused by the activation of the Thunderbolt chips:
I don't know if this is the issue you guys are experiencing, but just connecting a Thunderbolt accessory resulted in a 8°C spike which, in some ambient temperatures, is just enough to go over the idling threshold and make the fans spin up a bit. In the end I swapped my CalDigit TS3 with their USB-C Dock, back in the day when it was a real USB-C Dock. Now it's called "USB-C Pro Dock" and supports Thunderbolt, so I wouldn't really know what to recommend for new buyers.
TL;DR: If you don't need Thunderbolt capabilities but just an external monitor, Thunderbolt protocol can make your laptop heat up. Try to stick with USB-C docks if it's compatible with your configuration/monitor/refresh rate.
I don't know if this is the issue you guys are experiencing, but just connecting a Thunderbolt accessory resulted in a 8°C spike which, in some ambient temperatures, is just enough to go over the idling threshold and make the fans spin up a bit. In the end I swapped my CalDigit TS3 with their USB-C Dock, back in the day when it was a real USB-C Dock. Now it's called "USB-C Pro Dock" and supports Thunderbolt, so I wouldn't really know what to recommend for new buyers.
TL;DR: If you don't need Thunderbolt capabilities but just an external monitor, Thunderbolt protocol can make your laptop heat up. Try to stick with USB-C docks if it's compatible with your configuration/monitor/refresh rate.
Do you think that the "native" 4K-5K LG Ultrafine monitors that Apple sales perform better (heat wise) than our Dell, Sumsung and other brands?
P.S. This article is saying that the 21" 4K monitor uses USB-C instead of thunderbolt, so maybe it heats the system less?
" On the 4K model, one of these ports provides power to your MacBook at the same time as receiving the display signal, so all you need to do is plug in a single cable to use the monitor and charge the laptop. The other three USB-C ports can be used for various other peripherals, though they're limited to USB 2.0 because of Apple and LG's bandwidth-splitting solution for piping a 4K signal through USB-C. The 5K model doesn't have this limitation because it uses the faster Thunderbolt 3 interface, but that means it loses compatibility with the USB-C-only MacBook — you'll need a new Pro model to drive the bigger display."
https://www.theverge.com/circuitbre...he-lg-ultrafine-4k-is-a-great-macbook-monitor
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I don't use thunderbolt at home, only USB-C cables/adapters to connect my monitors. Makes no difference
@Appledoesnotlisten Are you close to an Apple Store? Just thinking you could book an appointment and take it in there to connect it up to their LGs?
Concur.
I’m seeing this with just
- Apple 96w with Apple Cable
- USB-C to DisplayPort 4K 60hz