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pneves1975

macrumors regular
Dec 4, 2018
113
59
Portugal
Lolol. My SP2 and SP3 would heat up even without monitors connected. Kkk.

I have a MBR 16" 2.4/6GHZ CPU and the 8GB GPU.

I don't know what's the fuss here, really. A role model MBP 15" of 2015" is less thermal efficient with my two monitors (4K and 2.6K) than my MBP 16". Even with no external monitors goes to 85 in a snap.
I am using that setup and typically get around 60º with iGPU model in clamshell mode. Using WebStorm, Safari with some tabs open, Mail, Word, Excel, Messages, Keynote, Music, Contacts. So how do you get 85?

PS: This is not an issue of the TB3+ dock either. These monitors connected the MBP 16" shows the same values. Rarely I ear the fans while coding if ever. They kick start at around 80º something mild noise, keep the temps under 90 for the most part, and go average noise at 90 up and than at 100 it becomes noisy. All natural.


Not saying that this cannot be optimised. If it can, Apple should do it ASAP. Just now is at 65, no fan noise, 5 apps, writing and debugging an angular app, CPU 90% idle.
If you find 65º normal in that scenario I don't. 90% idle without external monitor will set that machine to around 45-50 at most.

I am beating on a dead horse here. dGPU AMD does not play well with external monitors. On my 2018 machine battery on the same running programs goes from 7-8h to 2.5-3. How is this normal?
 

Nuno Lopes

macrumors 65816
Sep 6, 2011
1,374
1,276
Lisbon, Portugal
I am using that setup and typically get around 60º with iGPU model in clamshell mode. Using WebStorm, Safari with some tabs open, Mail, Word, Excel, Messages, Keynote, Music, Contacts. So how do you get 85?

So you get similar temps with the MBR 16” while connected with exmonitors and much better in clamshell mode correct?

Why is that odd to you?

EDIT: Hit 85 with music and building and debugging ... and if the bird process kicks in MBR 15. I’m no where near those temps doing the same thing, even with the bird process doing it’s thing, with the 16” model.. Meaning, the temps just stay there stable ... no to minimal fan noise.

Battery life it’s another issue. I only get 5 hours battery while coding in clamshell mode. Way out of the advertised 11. But that is not the theme of the thread. Mixing issues does not clarify the issues at hand.
 
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pneves1975

macrumors regular
Dec 4, 2018
113
59
Portugal
So you get similar temps with the MBR 16” while connected with exmonitors and much better in clamshell mode correct!

Why is that odd to you?

Dear Nuno,

I am referring to my 2015 15" iGPU model. I do not own a 16". I was replying to your "85 in a snap" sentence.

Another issue is that 65 in iGPU models is somehow different to 65 with dGPU since there is two chips throwing heat on different positions on the board leading to more heat on the unit itself.
 

Nuno Lopes

macrumors 65816
Sep 6, 2011
1,374
1,276
Lisbon, Portugal
Dear Nuno,

I am referring to my 2015 15" iGPU model. I do not own a 16". I was replying to your "85 in a snap" sentence.

Another issue is that 65 in iGPU models is somehow different to 65 with dGPU since there is two chips throwing heat on different positions on the board leading to more heat on the unit itself.

I get in a snap when the bird process kicks in (iCloud Sync) in the MBR 15. Something that does not happen with the MBR 16 while connected with the two monitors, much less in clamshell mode.

The fact is, that the 16 with more powerful CPU (Core i9) and dGPU is far more thermal efficient than the MBR 15 from 2015 Core i7 iGPU. Dont know about recent models. The later was considered a good MBP model, and now something far more efficient seams to be a problem.

At 60 in clamshell mode how is your MBR 15 from 2015 doing in terms of longevity?
 
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pshifrin

macrumors 6502a
Mar 14, 2010
519
387
Popped into the Apple Boylston St. store today, they have a base 16 connected to an XDR display. The laptop had logic pro and safari open. Put my ear to it and didn’t hear the fans blasting. Not a great test being a busy store I know...
 

decipherkl

macrumors member
Feb 17, 2020
66
33
Hi All,

I've similar issue with the base model with the 5300m dGPU and my external monitor is a Dell U2719dc which pushes 1440p@60Hz and able to provide 65W (I think) pd.

I have also tried various configurations to no avail. iStat would normally report ~60C with fan around 2k rpm and the dGPU will draw around 18W.

After hearing that some custom resolution with different refresh rate can lower the power draw of the dGPU, I tried using SwitchResX and set the resolution to 2040x1080 @24Hz (the most practical resolution without things becoming too large or distorted). Sure enough the power draw went down to approx 4W and the temperature sits around 47C in clamshell mode (do note that my ambient room temperature is probably closer to Florida since I live in the tropics).

I noticed that even 2040x1080 @60Hz will push it back to 18W. I haven't experimented widely with other resolutions and frequencies.

I hope this is useful. Now wonder if this is really

1) A design choice made by Apple
2) Unoptimized drivers
3) Inefficient hardware, especially the dGPU

I am hoping for a fix. Would appreciate if someone could find better resolution/frequency combo for this monitor :)

Hope this is useful for someone.

I found another two resolutions that are better than 2040x1080 @24Hz. They're 1080p50 PAL and 1080p60 NTSC (I realised these resolutions do not require SwitchResX) as they benefit from a higher refresh rate and also of their 16:9 aspect ratio rather than 17:9 :) Basically, with these settings, the total powerdraw in clamshell mode is halved to ~15W which is decent (approximate that of a bright LED bulb, haha).

I don't seem able to create custom 2560x1440 at lower refresh rates. May have another go at a later stage.

Interesting observations (but highly subjective):

1) Using Apple thunderbolt 3 cable (0.8m) results in higher powerdraw, ~2W more and ~1-2 deg C higher temperature but screen response appears to be faster than the Dell USB-C cable that came with my monitor, so scrolling through text is smoother

2) A Choetech USB-C to DisplayPort cable provides similar powerdraw to the Dell cable and similar response time to the Apple cable. But this has the disadvantage of requiring a charger and also the useful USB hub on the monitor become redundant

3) Dell cable has a very very slight lag (but noticeable) when scrolling through text
 
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Appledoesnotlisten

macrumors 6502a
Original poster
Dec 2, 2017
505
208
I've similar issue with the base model with the 5300m dGPU and my external monitor is a Dell U2719dc which pushes 1440p@60Hz and able to provide 65W (I think) pd.

I noticed that even 2040x1080 @60Hz will push it back to 18W. I haven't experimented widely with other resolutions and frequencies.
Let us know if you experiment with other resolutions and some of them decrease it to 4-11W!
 

Norbert Mikołajczyk

macrumors 6502
May 26, 2016
346
171
Hi, guys.

I have some update with the Lid closed mode.
Previously I had Unitek USB-C to DisplayPort 1.2 cable, with closed lid it was the same power draw 19-20W.
Now I bought new hi-end cable from Belkin USB-C -> HDMI, now with lid closed the power draw dropped to 5-6W!!!
I'm so glad I changed cables!

Some specs: Running LG 27GL850 at 1440p 99,88MHz, MBP16" in clamshell mode - power draw 5-6W, temp while listening to music and browsing is around 50-53C (10C degrees cooler!).
I also observe better and consistent UI fluidity in clamshell mode, when the lid is open the fps changes from choppy to smooth and vice versa, next driver issue?
 
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Idec50

macrumors regular
Feb 22, 2019
108
50
TX
Hi, guys.

I have some update with the Lid closed mode.
Previously I had Unitek USB-C to DisplayPort 1.2 cable, with closed lid it was the same power draw 19-20W.
Now I bought new hi-end cable from Belkin USB-C -> HDMI, now with lid closed the power draw dropped to 5-6W!!!
I'm so glad I changed cables!

Some specs: Running LG 27GL850 at 1440p 99,88MHz, MBP16" in clamshell mode - power draw 5-6W, temp while listening to music and browsing is around 50-53C (10C degrees cooler!).
I also observe better and consistent UI fluidity in clamshell mode, when the lid is open the fps changes from choppy to smooth and vice versa, next driver issue?

What do you get with the lid open?
 
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Norbert Mikołajczyk

macrumors 6502
May 26, 2016
346
171
What do you get with the lid open?

Fans are quiet 1900-1700rpm, right now CPU PECI temp is around 60-65C.
Listening to music and watching YouTube with no apparent changes with fans (maybe additional 100-200rpm?), temps 65-70C.
 

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gsbabil

macrumors member
Feb 4, 2020
66
29
Fans are quiet 1900-1700rpm, right now CPU PECI temp is around 60-65C.
Listening to music and watching YouTube with no apparent changes with fans (maybe additional 100-200rpm?), temps 65-70C.

Hi @Norbert Mikołajczyk,

I have similar results with lid closed ("clamshell" mode) you mention above with the same Belkin adapter as you. Thanks for sharing your results.

  1. Could you please confirm that you get 1900-1700rpm with lid open?
  2. Also, could you please share the resolution and refresh-rate of your external screen?
Thanks a lot.

P.S.

You can see my detailed results here. Thanks.
 

joelhinch

macrumors 6502
Oct 2, 2012
382
764
Fans are quiet 1900-1700rpm, right now CPU PECI temp is around 60-65C.
Listening to music and watching YouTube with no apparent changes with fans (maybe additional 100-200rpm?), temps 65-70C.
So per your screenshot, with lid open = 20w. Same as before.
[automerge]1582200341[/automerge]
USB-C to HDMI I got 20w straight away. Lid closed. Swapped to USB-C to DisplayPort. Down to 5w lid closed.
 

Norbert Mikołajczyk

macrumors 6502
May 26, 2016
346
171
Hi @Norbert Mikołajczyk,

I have similar results with lid closed ("clamshell" mode) you mention above with the same Belkin adapter as you. Thanks for sharing your results.

  1. Could you please confirm that you get 1900-1700rpm with lid open?
  2. Also, could you please share the resolution and refresh-rate of your external screen?
Thanks a lot.

P.S.

You can see my detailed results here. Thanks.
Hi,

Yes, 1850rpm Right, 1700rpm Left. 19W. 60-70C while writing this, checking some emails and time machine working in the background.

I switched both displays to default. My exernal lcd is gaming LG monitor with 144MHz refresh rate, it has three other refresh settings available using this cable (99.88, 75 and 59,88). It's weird but now ui animations are smooth. I'm sure there is some bug with the drivers, yesterday the animations were jerky.

I'm using different cable https://www.apple.com/shop/product/HKQ22ZM/A/belkin-usb-c-to-hdmi-adapter
 

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gsbabil

macrumors member
Feb 4, 2020
66
29
Hi,

Yes, 1850rpm Right, 1700rpm Left. 19W. 60-70C while writing this, checking some emails and time machine working in the background.

I switched both displays to default. My exernal lcd is gaming LG monitor with 144MHz refresh rate, it has three other refresh settings available using this cable (99.88, 75 and 59,88). It's weird but now ui animations are smooth. I'm sure there is some bug with the drivers, yesterday the animations were jerky.

I'm using different cable https://www.apple.com/shop/product/HKQ22ZM/A/belkin-usb-c-to-hdmi-adapter


Hi @Norbert Mikołajczyk,

Thanks for the updates. To clarify:


I switched both displays to default. My exernal lcd is gaming LG monitor with 144MHz refresh rate,

Finally, could you please share the actual resolution value when in "default" mode for your LG screen.

You can go to System Preferences.app > Displays > Display tab and move your mouse over the "Default" mode to find this. Alternatively, you could use EasyRes (free app) to find the exact value.


1582254146547.png


I'm trying to confirm the resolution because some of the previous posts reported that the refresh rate doesn't always have direct impact on the Radeon power draw, but the resolution does, which eventually impacts the fan RPM (and noise).

Thanks a lot once again.


P.S.

I don't see any major difference between the two adapters above myself - "Belkin USB-C to HDMI Adapter" seems to support HDCP 2.2 and a resolution of 4096x2160 @ 60Hz, while "USB-C Digital AV Multiport Adapter" seems to support 3840x2160 @ 60Hz. If you are aware of any other differences, please share. Thanks.
 
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Norbert Mikołajczyk

macrumors 6502
May 26, 2016
346
171
Hi @Norbert Mikołajczyk,

Thanks for the updates. To clarify:




Finally, could you please share the actual resolution value when in "default" mode for your LG screen.

You can go to System Preferences.app > Displays > Display tab and move your mouse over the "Default" mode to find this. Alternatively, you could use EasyRes (free app) to find the exact value.


View attachment 895318

I'm trying to confirm the resolution because some of the previous posts reported that the refresh rate doesn't always have direct impact on the Radeon power draw, but the resolution does, which eventually impacts the fan RPM (and noise).

Thanks a lot once again.


P.S.

I don't see any major difference between the two adapters above myself - "Belkin USB-C to HDMI Adapter" seems to support HDCP 2.2 and a resolution of 4096x2160 @ 60Hz, while "USB-C Digital AV Multiport Adapter" seems to support 3840x2160 @ 60Hz. If you are aware of any other differences, please share. Thanks.

Hi,

The resolutions are set to default on both displays.
MBP display refresh rate is set to 60Hz and the LG display is set to 99,88Hz.

Maybe it is something with the cables or external display or both...
For me it was cable as I wanted audio through the monitor and higher refresh rates to match my Radeon VII in my Mac Pro (144 Hz through DisplayPort 1.4, work and gaming machine). The new cable fixed for me the sound, higher refresh rates (99.88Hz is great enough for browsing and work) and power usage. Now I can use my MBP in clamshell mode and it is better behaving when the lid is open also.

I would wait for the 10.15.4 update, it brings gpu scaling fixes so they might have fixed the other issues as well.
 

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Intellinto

macrumors newbie
Feb 23, 2020
2
1
Here is my first and probably last video I did to share on maceumours, just dot this thread. Didi it with my phone and I'm Portuguese from Portugal, as an example of my daily experience with the MBP 16. So watch out for the heavy accent :)


What's your macbook specs ?
 

axlrod

macrumors newbie
Aug 14, 2017
8
3
Cables are DIGITAL, you will get NO change, its all random coincidence. As the radeon high side is still at 18+watt there are no difference ..
Sure you may get a few degrees difference from better power delivery on cables, but the main issue is that the radeon GPU goes to MAX wattage for no reason.
 
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Norbert Mikołajczyk

macrumors 6502
May 26, 2016
346
171
Cables are DIGITAL, you will get NO change, its all random coincidence. As the radeon high side is still at 18+watt there are no difference ..
Sure you may get a few degrees difference from better power delivery on cables, but the main issue is that the radeon GPU goes to MAX wattage for no reason.

Well the new cable helped me with the clamshell mode, power draw dropped from 19-20W to 5-6W ;)
 
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duddleyduddley

macrumors newbie
Jun 12, 2017
11
0
Quickly scanned posts and didn’t see information about your configuration.......

That said, have 16-inch MBP 64GB Ram 4TB SSD running two 4K 34” monitors...... with minimal fan noise and absolutely no cooling issues
 

Hibi Runrun

macrumors newbie
Feb 24, 2020
1
1
I just recently got the MBP 16 and have this as well. But knowing Radeon and Nvidia cards from windows I say this is normal and both Radeon and Nvidia team already knows about this for so long.
On Windows if you run 2 monitors at 1080p and 1 monitor is 59Hz and the other is 60Hz the GPU Ram freq. will bump up to max thus causing more power draw. Same thing will happen if you run 2 monitors with both 60hz but with different resolutions. But if you run 2 monitors with identical resolutions and refresh rate it goes back to power save mode on idle and thus drawing less power.
So using 2 identical monitors at a time or just using 1 monitor and closing the laptop is ideal.
 
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