Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

megalaser

macrumors 6502
Original poster
Nov 17, 2009
345
66
Hi, I have a 2013 Mac Pro (known as trashcan) - and I am trying any way I can right now to reduce the amount of electricity it uses, which is a lot! (compared to modern M1 Macs) - I have it plugged into a wattage meter and as soon as I turn it on it's burning over 150w (with no apps open yet) - this seems to me to be using a lot of power in what is essentially 'idle' . . . when I am using some apps and then go into sleep mode the power consumption does not drop, it's between around 150w and 180w usually . . . . my understanding is that when a Mac is idle (not doing anything or no apps open, or even sleep mode) the power consumption SHOULD drop right down - this never seems to be the case with my 2013 Mac Pro and I am wondering if anyone else with one has tried this? a power consumption meter plugged in (or even a close eye on the smart meter) and if the power consumption should or should not drop down to something reasonable when the Mac is either idle or sleeping? . . . I'd really like to know if mine is functioning correctly or if I need to be doing diagnostics of some kind to look into the power consumption. Thanks! ps: mine is: 6 core, 1TB and 64 GB RAM
 

megalaser

macrumors 6502
Original poster
Nov 17, 2009
345
66
Thanks. I've never seen it run at 43w . . . . without even logging into the OS it boots to around 150w
 

th0masp

macrumors 6502a
Mar 16, 2015
833
499
Pretty sure you are either measuring the wrong thing here or your computer doesn't idle nor sleep properly. Or you have tons of stuff connected to it that is burning electricity? Have you checked system temperatures and activity? There's an energy tab in activity monitor for example. Shouldn't show much usage at all in idle.

Btw. I've never measured mine with a device but would absolutely expect higher power usage at system start but none of that once it reaches the desktop/login screen.
 

arw

macrumors 65816
Aug 31, 2010
1,100
859
First of all, the 43W are completely unrealistic - never have I gotten anywhere close to it. At least not with Mojave or newer. I always wondered if they had the GPU downclocked for their initial testing and newer drivers unlocked the full potential at the cost of significantly higher idle power consumption.
Which GPU do you have?
150W are also way too high:
My 12-core D300 uses 75W in idle with a 5K display; iStat menus reports 59W.
My 12-core D500 uses 68W in idle with one 2K display; iStat menus reports 58W.
My 12-core D500 uses 94W in idle with two 2K displays (so +26W for a 2nd monitor 😱).
In sleep they use ~2W.
I‘d always login so you can see in Activity Monitor (or iStat menus) if the CPU and GPU are actually idle.
iStat menus also shows the (estimated) power consumption for CPU, GPU and total to give you an idea of the main electrical load.
Perform a SMC and PRAM reset, then check again.
Does the Mac heat up during sleep? If not, something is definitely wrong with your wattage meter.
BTW, the 12-core has a better performance-per-watt and runs cooler in idle (and I guess draws less power) than the 6-cores I had previously installed.

EDIT: updated values (Big Sur 11.7.1). The screenshot in iStat menus shows 59W but the Mac actually draws 75W.
EDIT2: updated values for D500 machine
 

Attachments

  • MP6,1_idle.png
    MP6,1_idle.png
    36.6 KB · Views: 66
Last edited:

megalaser

macrumors 6502
Original poster
Nov 17, 2009
345
66
Hi, Thanks for the replies, there's nothing wrong with the wattage meters, I have tried 3 and have a smart meter and the Mac Pro usually coasts along using around 150w. I did manage to get it to go lower by disconnecting all my devices, if I do that I can get it to go down to about 85w but then of course as I add each USB device (a couple of hubs) it creeps up . . . so it seems the UBS buses are the source of some of the power use (even though they are powered hubs) . . . 85w with nothing connected apart from a monitor is still higher than it should be (in an ideal world which may not exist) . . . I've tried the SMC reset (on this model it resets by simply unplugging the power cable for a while, then rebooting). The thing that makes me suspicious of a problem is that putting it into sleep mode or logging out does not reduce the power used . . . . .
 

megalaser

macrumors 6502
Original poster
Nov 17, 2009
345
66
ps: The mac does not seem to heat up during screensaver on/monitor off (sleep). I always have activity monitor open . . . . I should add that I have the D700 GPU running into a 4K monitor . . (tried it at lower resolution, no change to power consumption)
 

arw

macrumors 65816
Aug 31, 2010
1,100
859
ps: The mac does not seem to heat up during screensaver on/monitor off (sleep). I always have activity monitor open . . . . I should add that I have the D700 GPU running into a 4K monitor . . (tried it at lower resolution, no change to power consumption)
On my Mac, display off also doesn't reduce power consumption noticably.
Have you tried actually sleeping the Mac, not just the display?
pps: how do you define 'idle' ?
Mac powered on, display on but doing nothing (CPU/GPU 0% load).
 
Last edited:

megalaser

macrumors 6502
Original poster
Nov 17, 2009
345
66
On my Mac, display off also doesn't reduce power consumption for more than 2W.
Have you tried actually sleeping the Mac, not just the display?

Mac powered on, display on but doing nothing (CPU/GPU 0% load).
Thanks yes I've tried putting the Mac into sleep mode from the top Apple menu (power use the same, and also logging out) . . . there are always some background tasks running . . .
 

arw

macrumors 65816
Aug 31, 2010
1,100
859
Thanks yes I've tried putting the Mac into sleep mode from the top Apple menu (power use the same, and also logging out) . . . there are always some background tasks running . . .
When put to sleep, does the fan still run after a minute?
External devices definitely have a significant impact on the total draw of the Mac but in sleep, at least the Macs components should power down.
Sorry I couldn't be of more help...
If sleep is actually not working, I'd try finding the culprit for that:
In Activity Monitor you can add the column "prevent sleep" to see which process prevents it.
I don't know if a low-voltage RTC-battery can cause the same, but I guess it's merely responsible for crashes during/after sleep.
Finally I'd test consumption and sleep without any connected devices.
 
  • Like
Reactions: megalaser

th0masp

macrumors 6502a
Mar 16, 2015
833
499
If sleep is working you should see the power light pulsating. If that however stays solid then the computer isn't sleeping at all (you'll hear the fans and the case will stay warm in that case).

At any rate 150w sounds insane. Is the computer contributing to a botnet by any chance. ;)
 
  • Like
Reactions: megalaser

saudor

macrumors 68000
Jul 18, 2011
1,508
2,086
Are you running multiple monitors? AMD GPUs cant idle properly when there is more than 1 display connected.
My Hackintosh for instance idles at 46W with a single 4K display but as soon as i connect another display, it will jump to 70W+ and stay there. The GPU temps also rise significantly even when doing nothing.

The issue is made worse in macOS when you start doing scaling (e.g. running a 4K display in a "looks like 1440p" config --> this means the display is pixel doubled to 5K and scaled down to 4K)

150W is still high though.
 

WayneStewart

macrumors member
Oct 7, 2008
52
9
Vancouver, BC, Canada
I'm getting 65.9 watts on idle
a couple minutes after startup
No apps open
12 core 2.7 D700 500gb HD 1080 display
Only things attached is keyboard and mouse
If I put it into sleep mode it takes about a minute for the watts to drop but then I'm down to almost 0
 

megalaser

macrumors 6502
Original poster
Nov 17, 2009
345
66
I'm getting 65.9 watts on idle
a couple minutes after startup
No apps open
12 core 2.7 D700 500gb HD 1080 display
Only things attached is keyboard and mouse
If I put it into sleep mode it takes about a minute for the watts to drop but then I'm down to almost 0
Thanks, if I put mine into sleep mode the fans go off, monitor off and it looks just like a sleeping Mac . . . but the power consumption only drops a little bit (down to about 110 watts being used) from over 150w
 

megalaser

macrumors 6502
Original poster
Nov 17, 2009
345
66
Update: I have resolved the power consumption whilst sleeping issue (but it's still using a lot of power during 'idle') the sleep issue was caused by a Thunderbolt hub I had connected, when that's removed the Mac now sleeps and the power consumption is zero :) Now I'd like to find out how to generally lower power consumption when nothing is essentially happening and no apps are running . . .
 

arw

macrumors 65816
Aug 31, 2010
1,100
859
Update: I have resolved the power consumption whilst sleeping issue (but it's still using a lot of power during 'idle') the sleep issue was caused by a Thunderbolt hub I had connected, when that's removed the Mac now sleeps and the power consumption is zero :) Now I'd like to find out how to generally lower power consumption when nothing is essentially happening and no apps are running . . .
Thats something at least.
Try running the Mac Pro without any accessories (you got some reference numbers above) and only then start connecting devices. That should narrow it down.
If the “naked“ Mac Pro still uses too much, we‘d have to look at running processes.
If the culprit is an accessory, only you can decide if it‘s mandatory (a.e. if you only use the hub to connect monitors, a direct Thunderbolt/DP > video connection would be more efficient).
 

megalaser

macrumors 6502
Original poster
Nov 17, 2009
345
66
Thats something at least.
Try running the Mac Pro without any accessories (you got some reference numbers above) and only then start connecting devices. That should narrow it down.
If the “naked“ Mac Pro still uses too much, we‘d have to look at running processes.
If the culprit is an accessory, only you can decide if it‘s mandatory (a.e. if you only use the hub to connect monitors, a direct Thunderbolt/DP > video connection would be more efficient).
Thanks I tried that yesterday, with nothing connected it boots to the login screen using about 83 watts in power then once I log in and open a couple of things it creeps up from there . . . I did remove everything from the LaunchAgents and LaunchDaemon folders too and also removed everything from the loginitems pane in settings . . .
 

arw

macrumors 65816
Aug 31, 2010
1,100
859
Thanks I tried that yesterday, with nothing connected it boots to the login screen using about 83 watts in power then once I log in and open a couple of things it creeps up from there . . . I did remove everything from the LaunchAgents and LaunchDaemon folders too and also removed everything from the loginitems pane in settings . . .
Dependent on the connected display(s), 83W sounds very reasonable. Keep in mind:
- we‘re talking about 9 year old technology
- 7 years difference to M1
- it‘s still less than the base 2019 Mac Pro (101W idle acc. to Apple)
- it is completely normal/expected that this value increases significantly if you start opening apps
- it‘s a 130W CPU so even small activity increases consumption noticeably

In Activity Monitor you can check which process is putting strain on your CPU during times where you see the wattage spike/increase.
 
  • Like
Reactions: megalaser
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.