(2019) 16" is HOT & NOISY with an external monitor! :(

[chaiboy09]

Just another fun day at the office, using the internet!

This is crazy. I don't see this kind of fans for normal use (browsing and Youtube) even with lid open. It is always stay below 3000 RPM. Did I get a fixed piece in my refurbished model lol.....btw I am on 10.15.6 Catalina and using belkin adapter if that helps.....

 

[Grohowiak]

It depends how you see it. Good desktop will be always much faster and more efficient than laptop, no matter how you look at it. If your time is so precious and every second counts $$ then the solution is simple. Laptops are always with some trade-offs that's how I see it.

I'm waiting for arm cpus, if they will be as good as advertised then the whole industry gonna change.
By then my eGPU and laptop will earn money for itself hopefully, so no worries and regrets.
If they won't deliver something better than amd (intel is pretty much dead to me right now) I'll stay away from arm Macs and probably buy pc with amd cpu instead. I'm on macintel from the beginning so it will be hard to switch to Windows, but oh well, that's just machine to earn money, right?

Buying an imac now as a second computer when transition to ARM is happening is just a bad idea no matter how I look at it.
I can't move to windows because I develop for iOS. Wouldn't mind though. Win 10 is awesome.

 

[chaiboy09]

I got the same numbers and I’m using the same belkin adapter cable I’m happy with mine and planning to add the egpu to unlock full cpu potential as my cmp logic board went south... it will be silent too... I think it might be better in long term than 5600 investment, due to temps, full cpu potential without high fan rpms and of course silence while working on heavy projects and gaming.

1) yes, but in your case the difference could be 3-5c max lower only, we would need to investigate it further
2) yes and better performance

Great.....so you think that is normal temperatures for a low workload? I am also happy with my laptop....I feel it is not crazy hot and crazy noisy as other users are experiencing in the forum. Not sure why some MacBooks are behaving crazy and some are not.....however Radeon High Side @19 W when connected to external monitor seems to be an issue though and needs to be addressed. Not sure if older MacBooks had similar wattage. This is my first MacBook Pro

Was just worried if I had to go for 5600, but looks like I don't need to.

 

[Corncab44]

This is crazy. I don't see this kind of fans for normal use (browsing and Youtube) even with lid open. It is always stay below 3000 RPM. Did I get a fixed piece in my refurbished model lol.....btw I am on 10.15.6 Catalina and using belkin adapter if that helps.....

Nope it's a brand new i9 with 5500M. Always like this, fans never go below 3,500 when I have a few browser windows open and a couple apps, in clam shell. I also have an i7 5300m model that's slightly better but still hits the fans hard with normal use. On the i9 right now I'm use Volta set to max wattage of 27w, along with turbo boost off. The laptop is still snappy but the processor is only running at around 2ghz. Fans at around 3,200. if I open the laptop screen it will shoot up to 4,000 in a few minutes, then higher unless I've put leashes on the power supply.

 

[Daverru]

Mine is reporting 92% which I think is a little low for a relatively new device (I bought mine in December 2019). Or is this the result of the new battery health management introduced in 10.15.5?

This is probably the result of the new battery health management, right I tried to switch this setting off and got 98% instead of 92% after next battery charge.

 

[David58117]

Nope it's a brand new i9 with 5500M. Always like this, fans never go below 3,500 when I have a few browser windows open and a couple apps, in clam shell. I also have an i7 5300m model that's slightly better but still hits the fans hard with normal use. On the i9 right now I'm use Volta set to max wattage of 27w, along with turbo boost off. The laptop is still snappy but the processor is only running at around 2ghz. Fans at around 3,200. if I open the laptop screen it will shoot up to 4,000 in a few minutes, then higher unless I've put leashes on the power supply.

That's nuts, I have the same model (i9 5500M) and I'm definitely not seeing fans that high (as the picture you posted) unless I'm stressing it.

Have you checked Activity Monitor to make sure there's no errant process causing trouble? What apps are causing the high usage? And it's not Indexing still, right (open spotlight, type a few letters, look for "indexing.." in the results. At least that's how you use to check). ?

 

[chaiboy09]

Nope it's a brand new i9 with 5500M. Always like this, fans never go below 3,500 when I have a few browser windows open and a couple apps, in clam shell. I also have an i7 5300m model that's slightly better but still hits the fans hard with normal use. On the i9 right now I'm use Volta set to max wattage of 27w, along with turbo boost off. The laptop is still snappy but the processor is only running at around 2ghz. Fans at around 3,200. if I open the laptop screen it will shoot up to 4,000 in a few minutes, then higher unless I've put leashes on the power supply.

Hmmm.....that is really bad. Not sure why I don't see that behavior. May be the Monitor and the adapter make the difference? Just thinking out loud. Are you on 10.15.6? Let me try with non 4K monitors and see if I can get this kind of heat. I have 2 more days for return, just confused if I need to keep it or swap it lol.....my experience is decent (not ideal) with my Samsung 4K monitor though...

 

[LinkRS]

Howdy Folks,

This is a long thread LOL. If I am parsing this correctly, we are seeing two different problems concerning the MacBook Pro 16". One, is excessive fan noise and heat, and two is excessive power use (which results in higher fan speed, which means more noise, and obviously more heat) when connected to an external display. Personally, I have never used an Apple laptop plugged into an external display, I have a desktop PC for that, but my initial thought on this was "duh, of course the fans are on and the temp is higher, the dGPU is engaged." The fact that the fans are on (due to higher temp) and that the dGPU is on (required for external display) seems to not be a problem, but how the MBP is designed. I suspect that is part of why Apple Support keeps saying this is expected behavior.

What I am confused about, is what people expect is supposed to be happening? Ever since Apple went to the aluminum skinned notebook designs, the skin of the machines are part of the cooling system. The "fact" that the skin gets hot, is also expected behavior, and should not concern you, unless it gets too hot on places where you physically interact with the machine (such as palm rest, keyboard, perhaps even the bottom). Now what IS and SHOULD be concerning, is if the CPU and GPU are not getting sufficient cooling, leading to thermal throttling and shortening the life span of the electronics. The cooling system in the MBP should be designed to prevent that from happening, and if it isn't then you have a real issue.

The cooling system of the 16" MacBook Pro is an advertised feature: (taken from https://www.apple.com)
"The 16-inch MacBook Pro brings a whole new class of performance to the notebook. Thanks to a more advanced thermal design, the Intel Core i9 processor with up to 8 cores and 16 threads of processing power sustains higher performance for longer periods of time — and delivers up to 2.1 times the performance of a quad-core MacBook Pro. So whether you’re layering dozens of tracks and effects, rendering 3D models, or compiling and testing code, you’ll be doing it in no time flat."

So my question (and reason for this post) to y'all is are you seeing the system throttle (where the CPU and or/GPU lower clockspeed) below advertised clockspeeds (2.6 Ghz for i7, and 2.3 or 2.4 for i9) during use? If you are, then I think you have an issue you can get Apple to take a look at. IF your are just seeing a hot skin (on non-contact areas) and fan noise, with full performance, then you might be having different expectations than Apple. I purchased a BTO 16" MacBook Pro almost 2 months ago, but did not get a chance to really exercise it until last week. My system has the i9 2.3 GHz, 1 TB SSD, 16 GB RAM, and the 5500 8GB option, and I am currently NOT using BootCamp or any virtualization software. My primary apps (at the moment) are Unreal Engine (for game development, which uses Visual Studio Code and Xcode), and Diablo 3. I do not use Chrome, which is a battery sucking browser, but Safari, and run plugged in most of the time. Whenever I load Unreal Engine (or Diablo 3 ), the MBP switches to the dGPU, and temps jump to around 64C just idling (programs loaded, but not doing anything), and spike up to 99C frequently while actually pushing the GPU in Unreal Engine (temp reported from iStat Menus), at which time the fans spin up (to around 5400 RPMs), temps drop back down to 64C, and the fans drop back to ~4000 RPMs. Throughout all of this, I get no throttling, everything just works I have never checked the voltage of anything, but after reading this thread, I will take a look. For some strange reason, iStat Menus does not show my CPU clock speeds. I followed the instructions and installed the Intel app, but there is no difference. Regardless, unless I see my system start to throttle, I will just ignore the temp swings, as since I see no performance degradation, it is working as expected. Now if they are pushing the components too far, and causing a problem, then I have AppleCare+ for that .

Thanks!

Rich S.

 

[bomby0]

Howdy Folks,

This is a long thread LOL. If I am parsing this correctly, we are seeing two different problems concerning the MacBook Pro 16". One, is excessive fan noise and heat, and two is excessive power use (which results in higher fan speed, which means more noise, and obviously more heat) when connected to an external display. Personally, I have never used an Apple laptop plugged into an external display, I have a desktop PC for that, but my initial thought on this was "duh, of course the fans are on and the temp is higher, the dGPU is engaged." The fact that the fans are on (due to higher temp) and that the dGPU is on (required for external display) seems to not be a problem, but how the MBP is designed. I suspect that is part of why Apple Support keeps saying this is expected behavior.

What I am confused about, is what people expect is supposed to be happening? Ever since Apple went to the aluminum skinned notebook designs, the skin of the machines are part of the cooling system. The "fact" that the skin gets hot, is also expected behavior, and should not concern you, unless it gets too hot on places where you physically interact with the machine (such as palm rest, keyboard, perhaps even the bottom). Now what IS and SHOULD be concerning, is if the CPU and GPU are not getting sufficient cooling, leading to thermal throttling and shortening the life span of the electronics. The cooling system in the MBP should be designed to prevent that from happening, and if it isn't then you have a real issue.

The cooling system of the 16" MacBook Pro is an advertised feature: (taken from https://www.apple.com)
"The 16-inch MacBook Pro brings a whole new class of performance to the notebook. Thanks to a more advanced thermal design, the Intel Core i9 processor with up to 8 cores and 16 threads of processing power sustains higher performance for longer periods of time — and delivers up to 2.1 times the performance of a quad-core MacBook Pro. So whether you’re layering dozens of tracks and effects, rendering 3D models, or compiling and testing code, you’ll be doing it in no time flat."

So my question (and reason for this post) to y'all is are you seeing the system throttle (where the CPU and or/GPU lower clockspeed) below advertised clockspeeds (2.6 Ghz for i7, and 2.3 or 2.4 for i9) during use? If you are, then I think you have an issue you can get Apple to take a look at. IF your are just seeing a hot skin (on non-contact areas) and fan noise, with full performance, then you might be having different expectations than Apple. I purchased a BTO 16" MacBook Pro almost 2 months ago, but did not get a chance to really exercise it until last week. My system has the i9 2.3 GHz, 1 TB SSD, 16 GB RAM, and the 5500 8GB option, and I am currently NOT using BootCamp or any virtualization software. My primary apps (at the moment) are Unreal Engine (for game development, which uses Visual Studio Code and Xcode), and Diablo 3. I do not use Chrome, which is a battery sucking browser, but Safari, and run plugged in most of the time. Whenever I load Unreal Engine (or Diablo 3 ), the MBP switches to the dGPU, and temps jump to around 64C just idling (programs loaded, but not doing anything), and spike up to 99C frequently while actually pushing the GPU in Unreal Engine (temp reported from iStat Menus), at which time the fans spin up (to around 5400 RPMs), temps drop back down to 64C, and the fans drop back to ~4000 RPMs. Throughout all of this, I get no throttling, everything just works I have never checked the voltage of anything, but after reading this thread, I will take a look. For some strange reason, iStat Menus does not show my CPU clock speeds. I followed the instructions and installed the Intel app, but there is no difference. Regardless, unless I see my system start to throttle, I will just ignore the temp swings, as since I see no performance degradation, it is working as expected. Now if they are pushing the components too far, and causing a problem, then I have AppleCare+ for that .

Thanks!

Rich S.

A lot of us have older Macbook Pros to compare to. For example, my 2013 Macbook Pro 13" was completely silent and cool to the touch with the exact same monitor hooked up. It's absolutely insane Apple is saying this is "normal behavior" with a much newer and more expensive laptop. The experience is much much worse with my 16" than my old MBP so yeah most of us are super frustrated at Apple.

Of course it's not acting normally, Apple!

 

[Corncab44]

Howdy Folks,

This is a long thread LOL. If I am parsing this correctly, we are seeing two different problems concerning the MacBook Pro 16". One, is excessive fan noise and heat, and two is excessive power use (which results in higher fan speed, which means more noise, and obviously more heat) when connected to an external display. Personally, I have never used an Apple laptop plugged into an external display, I have a desktop PC for that, but my initial thought on this was "duh, of course the fans are on and the temp is higher, the dGPU is engaged." The fact that the fans are on (due to higher temp) and that the dGPU is on (required for external display) seems to not be a problem, but how the MBP is designed. I suspect that is part of why Apple Support keeps saying this is expected behavior.

What I am confused about, is what people expect is supposed to be happening? Ever since Apple went to the aluminum skinned notebook designs, the skin of the machines are part of the cooling system. The "fact" that the skin gets hot, is also expected behavior, and should not concern you, unless it gets too hot on places where you physically interact with the machine (such as palm rest, keyboard, perhaps even the bottom). Now what IS and SHOULD be concerning, is if the CPU and GPU are not getting sufficient cooling, leading to thermal throttling and shortening the life span of the electronics. The cooling system in the MBP should be designed to prevent that from happening, and if it isn't then you have a real issue.

The cooling system of the 16" MacBook Pro is an advertised feature: (taken from https://www.apple.com)
"The 16-inch MacBook Pro brings a whole new class of performance to the notebook. Thanks to a more advanced thermal design, the Intel Core i9 processor with up to 8 cores and 16 threads of processing power sustains higher performance for longer periods of time — and delivers up to 2.1 times the performance of a quad-core MacBook Pro. So whether you’re layering dozens of tracks and effects, rendering 3D models, or compiling and testing code, you’ll be doing it in no time flat."

So my question (and reason for this post) to y'all is are you seeing the system throttle (where the CPU and or/GPU lower clockspeed) below advertised clockspeeds (2.6 Ghz for i7, and 2.3 or 2.4 for i9) during use? If you are, then I think you have an issue you can get Apple to take a look at. IF your are just seeing a hot skin (on non-contact areas) and fan noise, with full performance, then you might be having different expectations than Apple. I purchased a BTO 16" MacBook Pro almost 2 months ago, but did not get a chance to really exercise it until last week. My system has the i9 2.3 GHz, 1 TB SSD, 16 GB RAM, and the 5500 8GB option, and I am currently NOT using BootCamp or any virtualization software. My primary apps (at the moment) are Unreal Engine (for game development, which uses Visual Studio Code and Xcode), and Diablo 3. I do not use Chrome, which is a battery sucking browser, but Safari, and run plugged in most of the time. Whenever I load Unreal Engine (or Diablo 3 ), the MBP switches to the dGPU, and temps jump to around 64C just idling (programs loaded, but not doing anything), and spike up to 99C frequently while actually pushing the GPU in Unreal Engine (temp reported from iStat Menus), at which time the fans spin up (to around 5400 RPMs), temps drop back down to 64C, and the fans drop back to ~4000 RPMs. Throughout all of this, I get no throttling, everything just works I have never checked the voltage of anything, but after reading this thread, I will take a look. For some strange reason, iStat Menus does not show my CPU clock speeds. I followed the instructions and installed the Intel app, but there is no difference. Regardless, unless I see my system start to throttle, I will just ignore the temp swings, as since I see no performance degradation, it is working as expected. Now if they are pushing the components too far, and causing a problem, then I have AppleCare+ for that .

Thanks!

Rich S.

The issue is that fans are ramping up for mundane tasks, largely because the dGPU suck up 20 watts automatically. Yes, you can get things done on the laptop with 5,000 rpm fans, and the processor doesn't get super hot.

That said, the issue with the radeon automatically taking up a lot of watts would presumably limit what the processor can do over an extended period if charging is capped at 100w. That's not a personal concern of mine, I'd prefer to just prefer to be able to turn off the dGPU (or have the huge power draw we see when plugged into an external) so that I can use the processor as I see fit.

 

[Corncab44]

Hmmm.....that is really bad. Not sure why I don't see that behavior. May be the Monitor and the adapter make the difference? Just thinking out loud. Are you on 10.15.6? Let me try with non 4K monitors and see if I can get this kind of heat. I have 2 more days for return, just confused if I need to keep it or swap it lol.....my experience is decent (not ideal) with my Samsung 4K monitor though...

The cooling on the 16 inch is good... I'm rarely ever above the 70s. But the profile is pretty aggressive at the lower end, and since Mac doesn't offer any power controls like windows, it's hard to stop this from happening unless you use third party apps. I think that I could live with this if it wasn't for the bug with the dGPU automatically turning on and drawing a lot of power when plugged in. I bought a $50 mophie cable and it made no difference. I updated to 10.15.6 and it made no difference.

If it doesn't bother you, keep the unit! Ignore this thread.

 

[LinkRS]

A lot of us have older Macbook Pros to compare to. For example, my 2013 Macbook Pro 13" was completely silent and cool to the touch with the exact same monitor hooked up. It's absolutely insane Apple is saying this is "normal behavior" with a much newer and more expensive laptop. The experience is much much worse with my 16" than my old MBP so yeah most of us are super frustrated at Apple.

Of course it's not acting normally, Apple!

Howdy bomby0,

I think you hit the nail on the head. Comparing your dGPU powered 16" to an iGPU powered 13" will paint a different picture. None of the 13" MBPs have had dGPUs, however some of the 15" did. The 13" MBP can use much less power than the 16", but of course the 16" can perform much better, at the expense of more power, heat, and therefor noise. Thanks for commenting

Rich S.

 

[kaans]

10.15.6 changed anything?

Meanwhile I've been ignoring the issue, so far so good, I also have an EXTREMELY noisy UPS in my room, just because my previous 2 MBPro's had swollen batteries, so I don't hear the fans over that jet engine UPS - I assumed the swollen batteries were electrical, but after this thread and keeping a closer eye on things, it was probably because of issues of this nature - devices run hot, sometimes bugs prevent sleep, when you keep the device connected, it likely results in premature wear and failure

I think 10.15.6 is 2-3C cooler? I almost never saw temps below 65C, now CPU is hovering around 62C while the GPU keeps a steady 65C - it could be a more aggressive fan profile tho

 

[LinkRS]

The issue is that fans are ramping up for mundane tasks, largely because the dGPU suck up 20 watts automatically. Yes, you can get things done on the laptop with 5,000 rpm fans, and the processor doesn't get super hot.

That said, the issue with the radeon automatically taking up a lot of watts would presumably limit what the processor can do over an extended period if charging is capped at 100w. That's not a personal concern of mine, I'd prefer to just prefer to be able to turn off the dGPU (or have the huge power draw we see when plugged into an external) so that I can use the processor as I see fit.

Howdy Corncab44,

<SNIP> Unpopular comment removed </SNIP> I did a little quick Googleing, looking for something to do what I propose, but the only thing I found was from a Hackintsosh site, so I won't post that here. Perhaps we can ask Apple to allow folks some kind of power slider, where you can reduce to power to the dGPU when you don't need the full performance, but not completely disabled. That way you could still use external screens. This is a common and easy tweak that you can do in Windows, but I am not familiar with a GPU underclock/undervolt utility for macOS?


Rich S.

 

[kaans]

If you read the thread a bit before imposing unpopular opinions you'd know that it's impossible on a hardware level

On battery, "sudo pmset -b gpuswitch 0" can be set to force iGPU always - sh*t programs like Pixelmator keeps dGPU always on, so having this is great on battery, since dGPU isn't any use anyway

 

[LinkRS]

If you read the thread a bit before imposing unpopular opinions you'd know that it's impossible on a hardware level

On battery, "sudo pmset -b gpuswitch 0" can be set to force iGPU always - sh*t programs like Pixelmator keeps dGPU always on, so having this is great on battery, since dGPU isn't any use anyway

Hi kaans,

Would doing that disable the dGPU? If the dGPU were disabled, apps like Pixelmator would not be able to turn it back on. I personally do not know how the Logicboard is wired, but in most PC laptop setups, the dGPU is routed through the iGPU to get to the display. So all video that is intended for display on the internal screen will always go through the iGPU. The situation is different, if the TB ports only provide output from the dGPU (which is what I assume you were suggesting I read from earlier in the thread), then disabling it would prevent you from using an external display, which is what folks want to be able to do. If that is the case, then there is no solution to the problem, as running the dGPU will always put a load on the system's thermal budget, causing fans noise and temps to rise. Even if you downclock the dGPU and its memory, it will still generate more heat than if it is off.

Rich S.

 

[thedocbwarren]

So more truth can't be stated. This is the reality. Personally I don't have the wild fan issue unless I push the system. Mine works well even pushed and, yes, it will engage the fans but I don't see performance issues. End of the day I do wish for desktop-like performance but given it's a thin laptop I don't expect it. I've had Mac Pros, and desktops for years and you can get babied with massive core sustain with no drop or high fan noise. Not going to happen on a laptop.

One thing I love is the portable massive power. When it was actually possible to leave the house I enjoyed a large VM with tons of compute going on. This is a solid awesome machine for sure. This is what I bought this thing for. That and I don't have a lot of space for lots of desktops at the moment otherwise I'd have a new cheese grater on my desk.

Hi kaans,

Would doing that disable the dGPU? If the dGPU were disabled, apps like Pixelmator would not be able to turn it back on. I personally do not know how the Logicboard is wired, but in most PC laptop setups, the dGPU is routed through the iGPU to get to the display. So all video that is intended for display on the internal screen will always go through the iGPU. The situation is different, if the TB ports only provide output from the dGPU (which is what I assume you were suggesting I read from earlier in the thread), then disabling it would prevent you from using an external display, which is what folks want to be able to do. If that is the case, then there is no solution to the problem, as running the dGPU will always put a load on the system's thermal budget, causing fans noise and temps to rise. Even if you downclock the dGPU and its memory, it will still generate more heat than if it is off.

Rich S.

 

[kaans]

It's not a solution to the problem, it's a native performance band-aid - if there was a native or custom-compiled way to disable Turbo too, I would do it, sadly it's not possible without a dev account that can sign kext's

There is no solution to the problem - that's the problem

I've been using "sudo pmset -b gpuswitch 0" for some weeks now, I didn't notice any ill effects, when you connect the device to the power, apps switch to dGPU just fine - on battery, the 16" Macbook acts like the 13" ones, so no unintentional hogs that reduce the supposedly 10 hour battery life to 2-3 hours

 

[Corncab44]

It's not a solution to the problem, it's a native performance band-aid - if there was a native or custom-compiled way to disable Turbo too, I would do it, sadly it's not possible without a dev account that can sign kext's

There is no solution to the problem - that's the problem

I've been using "sudo pmset -b gpuswitch 0" for some weeks now, I didn't notice any ill effects, when you connect the device to the power, apps switch to dGPU just fine - on battery, the 16" Macbook acts like the 13" ones, so no unintentional hogs that reduce the supposedly 10 hour battery life to 2-3 hours

Of course this only works when you aren't plugged into a monitor. You are forced to use the graphics card when you plug in -- hence the problem discussed in these 100+ pages.

 

[mrmachine79]

Thanks! Sounds awesome! Do you have any experience with running it on Windows?

Zero, sorry.
[automerge]1595021973[/automerge]

Hmmm.....that is really bad. Not sure why I don't see that behavior. May be the Monitor and the adapter make the difference? Just thinking out loud. Are you on 10.15.6? Let me try with non 4K monitors and see if I can get this kind of heat. I have 2 more days for return, just confused if I need to keep it or swap it lol.....my experience is decent (not ideal) with my Samsung 4K monitor though...

You're not seeing it because your usage is different. All these reports of X tabs open and a video are anecdotal. If you want to compare two systems to see if only one has an issue or not, you need to devise a consistent repeatable test. A fresh install of the same version of Catalina with zero menu bar apps or launch items. Run the same tabs or videos in the same browsers for the same amount of time etc.

 

[sco]

What I am confused about, is what people expect is supposed to be happening?

The Radeon to work reasonably. In my case with the 5500M I got 20W usage with my 4K displays plugged in. Now if I rotated 1 display by 90 degrees or 180 degrees it dropped to 8W. So there was 12W of wasted power for no good reason. It makes no sense why rotating the display reduced power usage when in fact it would have increased the work for the GPU.

I need the portable powerhouse and I accept the fan noise when the machine is busy doing something. I wasn't happy giving up 12W of the power budget for no good reason. I shouldn't have needed to upgrade to the 5600M to get reasonable GPU behaviour, but I did... my time is money and I'd already burnt a lot of hours trying to get the 5500M to behave reasonably.

 

[decipherkl]

This is probably the result of the new battery health management, right I tried to switch this setting off and got 98% instead of 92% after next battery charge.

Thanks

 

[dukee101]

In my case with the 5500M I got 20W usage with my 4K displays plugged in. Now if I rotated 1 display by 90 degrees or 180 degrees it dropped to 8W.

Whoa! This is a very important finding. Simply rotating one of your 4K displays 90 degrees would cause a 12W power drop on the dGPU?? Does anyone else have similar evidence?

 

[Humai]

Whoa! This is a very important finding. Simply rotating one of your 4K displays 90 degrees would cause a 12W power drop on the dGPU?? Does anyone else have similar evidence?

I can confirm that this trick does not work with a single external monitor. I have an i7/5300M on 10.15.5 connected to a Dell UP3216Q. 90 and 180 degree rotations made no difference to the GPU power consumption of 17 - 18 watts. If I close the lid and operate with just the Dell monitor, GPU power drops to about 4 watts.

 

[sco]

I can confirm that this trick does not work with a single external monitor. I have an i7/5300M on 10.15.5 connected to a Dell UP3216Q. 90 and 180 degree rotations made no difference to the GPU power consumption of 17 - 18 watts. If I close the lid and operate with just the Dell monitor, GPU power drops to about 4 watts.

That's in line with what I saw. Single monitor in clamshell was OK. Once I added a second monitor (exactly the same brand, settings and connected the same way - displayport via a different thunderbolt bus on other side of the MBPro) the power usage jumped until I rotated one of the monitors.

Rotating both monitors caused power usage to drop also. My educated guess (as a software developer) was that the rotation was triggering a different path through the downclocking decision logic and thus maybe bypassing a bug. Others have reported better behaviour in Bootcamped Windows with exactly the same setup they had for MacOS. I never tried this myself before returning the 5500M. But it is more evidence that behaviour may be partially due to a bug in the video drivers but that said maybe the scaling behaviour in MacOS means the GPU is driven differently.

The 5600M can drive these two displays (in standard rotation) at less than 10W suggests some sort of bug also. As I type this email I'm driving the 2 x 4K displays, the internal display plus a 1920x1200 display and the 5600M power usage is under 9W. This arrangement was 24W+ on the 5500M. 5600M stats below: