Interesting, I just got my usb-c to display port cable, I tried on the right side and saw the higher wattage. Will try on the left side!
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(2019) 16" is HOT & NOISY with an external monitor! :(
- Thread starter Appledoesnotlisten
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To add some more weirdness onto the pile.
Doing some extra messing around with settings I noticed that if I set my external monitor to 'Default for display' - which is 3440x1440@60hz + clamshell - the Radeon High-Side is ~7-8W.
If I set the external monitor to scaled 3440x1440@30hz (with HDR on or Off) + clamshell = 18W.
If I set the monitor to scaled 3440x1440@60HZ (HDR no longer an option) + clamshell = back to 7-8W.
If I set to scaled 3840 x 2160@30hz + clamshell = 6-7W.
Now, I don't know what anyone would do with this information - but it certainly seems like if you dial into the perfect combo of:
Right external display + right cable + right settings + clamshell.....maybe your GPU won't need to dissipate 18W just to sit around.
Doing some extra messing around with settings I noticed that if I set my external monitor to 'Default for display' - which is 3440x1440@60hz + clamshell - the Radeon High-Side is ~7-8W.
If I set the external monitor to scaled 3440x1440@30hz (with HDR on or Off) + clamshell = 18W.
If I set the monitor to scaled 3440x1440@60HZ (HDR no longer an option) + clamshell = back to 7-8W.
If I set to scaled 3840 x 2160@30hz + clamshell = 6-7W.
Now, I don't know what anyone would do with this information - but it certainly seems like if you dial into the perfect combo of:
Right external display + right cable + right settings + clamshell.....maybe your GPU won't need to dissipate 18W just to sit around.
I don't believe that is a viable option in regards to external displays. I could be wrong, but I am pretty sure you cannot remove the dGPU from the equation when you're using an external monitor.
gSwitch and similar tools are great for when you're on battery and want to try and stop the dGPU from sucking juice, but I don't know that they are useable in this scenario.
Ah yeah - checked out the GH repo
Why does the app go back to dynamic switching when a display is plugged in?
Unfortunately your mac is designed such that in order to use an external display, it has to use the discrete graphics card. And since you plugged in the cable I'm assuming you want to use the display.
Seems odd that the 16" needs the dGPU spun up to drive an external screen when the 13" doesn't, as it clearly doesn't have a dGPU
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I've read the first 33 pages of this and tried to take some notes and figure out what's going on.
Claim: The 18 W is a red herring!
(Someone please fact-check me based on the below lol)
The few people who are saying 'there is no problem' with their setup (fans inaudible) that have also posted screenshots showing the Radeon GPU power draw are still showing 18 W while their fans are bottomed out at 1800rpm. All that I saw did seem to claim that this was a stable state, i.e. it was running that way for at least a few minutes. NOBODY I have seen post reports anything less than 18 W draw with 1 or more external displays connected + lid open, regardless of whether their fans spin fast or not.
This means that yes, their laptop is drawing more power than necessary and that is a problem, but somehow the cooling is adequate and the heat remains low so the fans remain low. That makes me think that the real issue is a manufacturing defect in the cooling solution.
(I had earlier claimed that 18 W dissipating as heat was bound to cause the fans to spin up. Seems I was wrong.)
The thing that's confusing people is that when you have the lid closed (so running on external monitors only), the GPU will draw either 5 W base or 18 W base and it doesn't seem to be logical, e.g. running at 60 Hz draws 18 W while the same resolution running at 144 Hz draws only 5 W. But as I said, 18 W for the 'happy customers' does not result in excess heat and fan noise.
A few interesting sources:
Anyone disagree with the above?
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Additionally, people claiming that 'if it can't even drive 1 1080p external display without overheating then how can it handle 3 5K XDR displays' are possibly misleading. The GPU is just doing wasted work, so far all of the evidence I've poured through does not suggest that plugging in more monitors at higher data rates causes the machine to choke or generate appreciably more heat.
Claim: The 18 W is a red herring!
(Someone please fact-check me based on the below lol)
The few people who are saying 'there is no problem' with their setup (fans inaudible) that have also posted screenshots showing the Radeon GPU power draw are still showing 18 W while their fans are bottomed out at 1800rpm. All that I saw did seem to claim that this was a stable state, i.e. it was running that way for at least a few minutes. NOBODY I have seen post reports anything less than 18 W draw with 1 or more external displays connected + lid open, regardless of whether their fans spin fast or not.
This means that yes, their laptop is drawing more power than necessary and that is a problem, but somehow the cooling is adequate and the heat remains low so the fans remain low. That makes me think that the real issue is a manufacturing defect in the cooling solution.
(I had earlier claimed that 18 W dissipating as heat was bound to cause the fans to spin up. Seems I was wrong.)
The thing that's confusing people is that when you have the lid closed (so running on external monitors only), the GPU will draw either 5 W base or 18 W base and it doesn't seem to be logical, e.g. running at 60 Hz draws 18 W while the same resolution running at 144 Hz draws only 5 W. But as I said, 18 W for the 'happy customers' does not result in excess heat and fan noise.
A few interesting sources:
- @ascender claiming running with 4K monitors and lid open and no excessive fan: https://forums.macrumors.com/threads/16-is-hot-noisy-with-an-external-monitor.2211747/post-27999175
- @am2am clearly showing 19W Radeon draw with silent (1800rpm) fans - not clear how long this was left running, though. https://forums.macrumors.com/threads/16-is-hot-noisy-with-an-external-monitor.2211747/post-28028111 - also note their ambient temperature was reported as around 19C, which is fairly cool. Mine is more like 25C and I do see a problem, but it's unclear if 6 degrees C is enough to cause this problem.
- @robvas posting screenshots of them hooking up a lot of external monitors with the lid open and claiming no fan noise - no screenshots proving Radeon power draw though, but I suspect it's >18 W. Can you please confirm @robvas? https://forums.macrumors.com/threads/16-is-hot-noisy-with-an-external-monitor.2211747/post-28137634
- @Quu reporting 18 W draw with internal + external monitors but low fan speeds - 2000-2400rpm. https://forums.macrumors.com/threads/16-is-hot-noisy-with-an-external-monitor.2211747/post-28095494
- @TimothyB posting clear screenshots of having external monitor plugged in, watching YouTube for 5 mins, drawing 18W from the Radeon and fans staying at 1800rpm. https://forums.macrumors.com/threads/16-is-hot-noisy-with-an-external-monitor.2211747/post-27997896
Anyone disagree with the above?
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Additionally, people claiming that 'if it can't even drive 1 1080p external display without overheating then how can it handle 3 5K XDR displays' are possibly misleading. The GPU is just doing wasted work, so far all of the evidence I've poured through does not suggest that plugging in more monitors at higher data rates causes the machine to choke or generate appreciably more heat.
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I am considering using the post-COVID store closure return policy to return my 16-inch that I purchased in March and wait until the fall for the second gen 16-inch. It's just crazy that the fans start going on your $3k computer when you plug in a 1080p monitor. Apple isn't going to care about this until it hits them where it hurts and we're doing ourselves no favors by just living with it.
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engineering flaw, just show apple and be like no Mac has ever done this, you guys advertised this has next gen cooling and look at this... technically id say its false advertisement.
Certainly they will give you a new 16" if they can't balance the igpu with the dgpu
"More advanced thermal architecture enables faster processing. The thermal architecture in MacBook Pro has been completely redesigned, featuring larger impellers with improved fan blades for optimal airflow and more heat-dispersing fins for more effective cooling. The resulting gain in cooling capacity allows MacBook Pro to deliver up to 12 watts more maximum sustained power." - Apple
Its all right there.
But being devil's advocate here, does it not deliver what you quoted tho? It doesn't overheat and it doesn't throttle. The fans may be noisy, but it does what's advertised. I get it's frustrating, not ideal, and something is up, but it's not "faulty"
Patching over this with a 'low power mode' is not really acceptable given the price. Given that people are returning their macs twice, three times, or more, and still getting duds, but some people have no reported issues, or get lucky on their second replacement, tells me that there is a minority of working stock in the warehouse, where we'd never be even having this conversation if they were the norm.
But now that I'm aware of how easy it is, I'll definitely be using Turbo Boost Switcher as I work. I don't mind a small amount of sluggishness in exchange for near silence - and when I need something in a hurry like a render I'll just turn it back on.
I'd agree that being able to drive a monitor shouldn't put it in 'low power mode', but it would still be nice to essentially throttle your laptop so it stays quiet.
I think so, the intel 630 is designed to push 4k x3 yet apple defaults the system use a dedicated gpu is not a properly utilized or designed system imo.
We shouldn't be expected to kneecap our $3k computer with a kludgy, third-party app like Turbo Boost Switcher just to keep the machine from turning into a flattop griddle when driving a 1080p monitor. It's unacceptable. Crappy drivers and iffy hardware just ain't gonna cut it if we have to pay the Apple tax.
Did anyone ever run geekbench with turbo turned off? Im just wondering what kind of cpu power one gets when using this workaround.
Agreed, that's why mine's going back for a dice-roll replacement. Maybe twice. But even if I get a 'working one' I'll still be using Turbo Boost Switcher on any computer I get because I might as well save my hardware's life by running it cooler unless I feel like I'm being slowed down by it. #savetheplanet
By the way this is one of the most interesting pieces of posts of the last few pages. It's the only piece of evidence of what is probably causing the spike in power consumption. Of course any Apple engineer worth their salt should already be knowing this right now, but for the rest of us left in the dark it's probably a sign that indeed things are running hot for some driver fault.
Good summary.
I am the lucky one without overheating problems with external monitor, but I can confirm that Radeon is drawing 18W with external monitor (~5W in clamshell).
This is strange and I cannot find an explanation for it other than crapalina effect.
BUT it does not necessary means that the performance of the machine is impacted by this.
I did a test - export short 4k movie from fcp - without and with external monitor (not in clamshell - with internal and external screens on). I did it twice (without and with x2 to verify that the results are comparable). You can see the details in the attachment below.
Without external monitor Radeon was drawing approx 25W during 2 mins (yellow on graph)
With external monitor it was approx 26-28W during 2 mins. (red on graph)
The fans in both cases reaches approx 3k rpm and after the export they went down to minimum 1.8k rpm after approx 2 mins (maybe 2m30s with external monitor connected - slightly slower but still reach the minimum). My ambience temp is around 22stC.
I've measured the time for each export - the difference were below 1s (approx 2m03s total)
Conclusion: Radeon may be drawing 18W unnecessary with external monitor while idle, but as soon as you start using your machine - under the load, the power draw is nearly the same without and without external monitor (2-3W difference) - the situation should not be impacting your workflow with external monitor.
This machine is designed to perform - not to stay idle. Apple delivers on this IMO.
A 2 min export is way too short to actually get all the cooling system and chassis up to temperature. That's when you're gonna get throttling. Leaving apart the fact that some users may be doing workflows that don't involve the GPU much at all (like a lot of the Adobe Creative Suite, which is poorly optimized to the newer GPUs), all that power/heat is effectively wasted.
OK, so the big question is ..... has anyone actually experienced throttling in these scenarios? Yes it draws more power, gets hot and makes noise, but does it throttle?
Can you please try running cinebench on loop via min test duration AND luxmark GPUs stress test (loops) at the same time for 10 minutes?
Do this with just the internal display and then with the external display and lid open which triggers 18W Radeon at idle.
While the tests are running, watch Intel power gadget to see if both frequency and power/PKG are able to sustain a stable level (and not what the levels are). If possible, a screen recording showing Intel power gadget for a minute, after running the stress tests for a few minutes would be great.
This should test and confirm (or disprove) that even though hot and noisy, performance is not lost (I don't believe this will be true).
I get the 16" MBP is designed to offer the fastest experience.
But having loud fans by just connecting an external monitor is bad design.