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(2019) 16" is HOT & NOISY with an external monitor! :(
- Thread starter Appledoesnotlisten
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Don't forget to ask for the monitor and cables as well (and I'm only half-joking).
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I agree that dual monitor (internal and external) users are not a majority, but note that some users are reporting high power draw even in clamshell mode. Also, the fan issue seems to be an issue for some and not for others, possibly for different reasons (e.g. fans aren't spinning fast, or the noise doesn't bother them).
As for the high wattage, that just can't be good. I can't explain why this doesn't always result in higher temperatures, but I figure there's got to be more heat under those conditions, and I can't see that being good for internal components. I like to keep my Mac computers for a long time (5+ years), and I am concerned that this will significantly shorten their lifetimes.
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Quick update - I went out and got an A-Logic USB-C to display port adapter and found no difference in behaviour when connected to a single external monitor via display port.
The issue remains, connecting to an external monitor drives GPU power usage quite high and the fans come on full blast.
Have also discovered to my horror that in Bootcamp even with no external monitors connected the GPU power draw and memory clock speed are extremely high
Not sure when this happened but it's a regression to previously when the memory clock/power draw were low until I connected an external display.
If I drop the resolution down to 1920x1080 the memory clockd rops to 190mhz and power draw goes way down as a result.
this is getting screwier by the day.
Decided to try updating to latest bootcamp drivers just to see if it makes an impact,
850W power consumption? 737 degrees junctin temperature? WTF is going on here? Maybe AMD multiplied by 10 haha.
The issue remains, connecting to an external monitor drives GPU power usage quite high and the fans come on full blast.
Have also discovered to my horror that in Bootcamp even with no external monitors connected the GPU power draw and memory clock speed are extremely high
Not sure when this happened but it's a regression to previously when the memory clock/power draw were low until I connected an external display.
If I drop the resolution down to 1920x1080 the memory clockd rops to 190mhz and power draw goes way down as a result.
this is getting screwier by the day.
Decided to try updating to latest bootcamp drivers just to see if it makes an impact,
850W power consumption? 737 degrees junctin temperature? WTF is going on here? Maybe AMD multiplied by 10 haha.
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Clamshell mode is fine, and it's also fine with a usb-c to hdmi converter.
As long as it's not two monitors connected in clamshell...
HDMI to USB C cable
just tried clamshell, temp dropped to 70c but fans are still going strong at 5500 rpm and about same noise level
Let your macbook have a breather and cool down completely then run in clamshell and see what happens - most likely the temperature won't go up anymore (not that I think this is an acceptable solution).
it's been about 15 min since starting clamshell, temp keeps dropping but fan stays the same.
i will update if it changes.
but in anycase I didn't bought a $3200 machine to keep it close all the time so seems like it's going back to apple again..
Even though overall CPU load is 10-15% fans could still be high if a single CPU core is high utilisation and frequency? Check activity monitor and Intel power gadget.
Reset SMC 3-4 times and stop using 3rd-party software to switch TurboBoost or change fans speed. Basically, just use your 16" MacBook as-is.
I found out Macs Fan Control caused my fans to stay on full blast, both of them, at all times, regardless of temperature, across shutdown/restart/Bootcamp, etc...
So something in the SMC is not happy with 3rd-party software.
What about 1080P monitors? or 2K. Do you still see the 20W on those monitors? I plan to buy Imac Pro or Using low-quality monitors with MBP.
People have seen 20W with 1080p and any other lower resolution monitors, at all refresh rates. You can scroll back probably the last 30 pages or so to read about their experience.
I personally also see 20W if I have my MacBook's lid open and an external display is connected. The fans do go a bit above the usual "silent" threshold (1800RPM), but I'll either be watching a video or on a Zoom call so fan noise would be drowned out.
I'm personally not bothered by this as I leave my MacBook in clamshell almost all the time while at the desk, since my single ultrawide monitor is enough for me, but... that's just me.
Consider your usage carefully before committing. Basically, I guess based on feedback the only way you'll for sure get 5W idle right now seems to be that:
1. You have to leave the MacBook in clamshell
2. You need a Thunderbolt 3 or USB-C display
If either of the above are not acceptable, then wait until Apple addresses this issue.
I personally also see 20W if I have my MacBook's lid open and an external display is connected. The fans do go a bit above the usual "silent" threshold (1800RPM), but I'll either be watching a video or on a Zoom call so fan noise would be drowned out.
I'm personally not bothered by this as I leave my MacBook in clamshell almost all the time while at the desk, since my single ultrawide monitor is enough for me, but... that's just me.
Consider your usage carefully before committing. Basically, I guess based on feedback the only way you'll for sure get 5W idle right now seems to be that:
1. You have to leave the MacBook in clamshell
2. You need a Thunderbolt 3 or USB-C display
If either of the above are not acceptable, then wait until Apple addresses this issue.
My display is HDMI, and I connect it using the Apple adaptor.
In clamshell, it works perfectly. (Fans below 2K-2.5K)
Not everyone is as lucky as you are. I got told off for just saying "this issue does not affect everyone" (check the last page).
Let's just say those who are affected by it are very frustrated that they spent a lot of money for nothing.
Those who are not affected never provide iStat details
I assume they are affected but do not see the issue.Those who are not affected never provide iStat details
I have provided pages of iStat details. Let's just say those don't matter. But here's another one just to prove the point:
Again, not everyone is affected. I guess someone will jump in and tell me off again, but whatever. I understand the frustration, but this thread has become more about "there's an issue, let's continue to cry" rather than "there may be a solution, let's find it".
Clamshell mode work for almost everyone doesn't it?
I don't have iStat Menu, but when using it open lid, fans go above 5K. when using it closed, fans don't go above 2-2.5K.
I'm measuring this with Turbo Boost Switcher, but Turbo Boost is always enabled in both cases.
After reading ~15 pages of this thread, that's the sense I'm getting. I just wish I knew what was causing high power draw for those in clamshell mode with one external monitor before I purchase a 16-MBP. At first I thought it could be HDMI, but I think I've seen users post that they were fine with HDMI. I thought that perhaps opening then closing the laptop left it stuck with a high power draw, but your experience say otherwise. I also thought it could be only certain video cards, but nope.
I can wait a bit longer (mid-July is probably my limit, depending on build lead times) for a software fix or an updated laptop that is 'fixed'.
I have EXACTLY this behaviour on a 2019 15". I recommend installing the istat additional component or Intel power gadget that allows you to monitor CPU frequency as well. You'll probably see that it has dropped to 800mhz or 1.4ghz when kernel task is high.
I suspect that even though CPU temp is low, either VRM temp is high or just too much power is being used by GPU, so CPU power is reduced dramatically. I've seen in Intel power gadget CPU power gonas low as 7w at the extreme end while under CPU load (cinebench) and GPU also doing some work (discord video chat or luxmark benchmark), but typically it goes down to 23-26w.
I am working around this issue with a razer core X eGPU and sapphire pulse rx 5500 xt graphics card. This is slightly louder (28dB at 2 feet) than the Mac with internal display at idle but much quieter than the Mac with max fans.
The dGPU is still used, but only draws 0-5w typically to drive the external display instead of 15w min.
There are some quirks with using an egpu eg restarting apps when disconnecting it if you need to go portable, but it allows my CPU to now sustain 50w power and in normal use CPU frequency now hovers around 3.5ghz with peaks up to 4ghz. Under sustained heavy CPU (cinebench) AND GPU (luxmark) tests, it can now sustain around 2.7-3ghz indefinitely with no kernel task issues.
I'm going to run the same tests on a 16" next week.
If you still have issues even in clamshell mode you may like to do one of 2 things
1) Change your output resolution to that monitor
2) Change the refresh rate at your preferred resolution
Hopefully changing these two parameters (either or in combination) will help you achieved lower dGPU power draw. That's my experience so far with only one external monitor - Dell U2719dc, a 1440p monitor. Default 1440p @60Hz didn't work in clamshell mode and I had to lower resolution to 1080p for it to work. Changing refresh rate to 73Hz allowed me to work at 1440p in clamshell mode. Some experimentation is needed.
Same issues with a 16" under macOS. Got curious if results would be different with Windows and newer Radeon drivers.
Using bootcampdrivers' Adrenalin April 2020 Blue Enterprise edition (Best for MBP 16 inch and Radeon 500 series iMacs) the laptop was not stable and would crash whenever loading a game. Downgrading to Adrenalin January 2020 Red Gaming edition (Best FPS in games) made everything work fine.
Laptop in clamshell mode with a LG 32UD99 (4K60) over USB-C was drawing 4W in Windows vs. 5-6W in macOS and more significantly 14W when the laptop is open and connected to the external display vs. 20-21W in macOS.
An interesting note would also be that one display makes the dGPU work at 190MHz while adding another high resolution display drives it up to 1472MHz. Although unlikely, if the 5300M/5500M have the hardware capacity to drive two hi-res displays without having to ramp up to a higher power state maybe there could be a fix in the future. Would most likely return and see if things change with RDNA 2.
PS: Wattage reporting was working fine, unlike @_meds' report. Perhaps it would be drivers difference?
Using bootcampdrivers' Adrenalin April 2020 Blue Enterprise edition (Best for MBP 16 inch and Radeon 500 series iMacs) the laptop was not stable and would crash whenever loading a game. Downgrading to Adrenalin January 2020 Red Gaming edition (Best FPS in games) made everything work fine.
Laptop in clamshell mode with a LG 32UD99 (4K60) over USB-C was drawing 4W in Windows vs. 5-6W in macOS and more significantly 14W when the laptop is open and connected to the external display vs. 20-21W in macOS.
An interesting note would also be that one display makes the dGPU work at 190MHz while adding another high resolution display drives it up to 1472MHz. Although unlikely, if the 5300M/5500M have the hardware capacity to drive two hi-res displays without having to ramp up to a higher power state maybe there could be a fix in the future. Would most likely return and see if things change with RDNA 2.
PS: Wattage reporting was working fine, unlike @_meds' report. Perhaps it would be drivers difference?
I have provided pages of iStat details. Let's just say those don't matter. But here's another one just to prove the point:
Again, not everyone is affected. I guess someone will jump in and tell me off again, but whatever. I understand the frustration, but this thread has become more about "there's an issue, let's continue to cry" rather than "there may be a solution, let's find it".
Unless I'm mistaken it looks like you're running in clamshell mode? In which case that is pretty consistant with my experiences as well, it's when I'm trying to run more than one display things go wrong.