Plugged in Kila Watt and realized at idle or doing simple tasks it draws 270-300watts. In my MacBook Pro M1’s it only uses 20watts max. When I play games or use GPU it adds another 100-300watts totaling 370-600watts.

If I do any simple tasks is there anyway for me to downclock the CPU so it can go down to as low as what laptop does, or is this the only way? I just realized I might be spending at least $30-40/month in electricity using my Mac Pro only doing simple tasks.

Thanks.

Maybe your RTX 3090 inside is never "off" when you are on Mac OS.

The RTX 3090 may indeed not be properly managed from the power saving point in the Mac OS. But then 270W-300W idle power is not totally out of proportion compared to the figures given by Apple (from 100 to 300W idle for the MP7,1m depending on the config).

It may be more power efficient to have a dedicated Windows machine which is switched off when not used and trim down your MP7,1 to what is required in macOS. But then you're going to pay much more for that machine than what you could possibly save in elictricity bills.

The 16-core version with the Radeon 580 idles at about 90w under MacOS and 70w under Windows. Windows seems to be better at clocking down to lower levels when there is nothing going on.
But it's a big Xeon chip, it will never be like a new M1 - my MBP 16" 10/32 with 64GB runs at 6w idle.

Dominic

Mac3Duser said:

Maybe your RTX 3090 inside is never "off" when you are on Mac OS.

Happens even when RTX3090 is unplugged or out of Mac Pro (with 6900XT or W5700X). I believe it’s the CPU that is driving this power.

fiatlux said:

The RTX 3090 may indeed not be properly managed from the power saving point in the Mac OS. But then 270W-300W idle power is not totally out of proportion compared to the figures given by Apple (from 100 to 300W idle for the MP7,1m depending on the config).

It may be more power efficient to have a dedicated Windows machine which is switched off when not used and trim down your MP7,1 to what is required in macOS. But then you're going to pay much more for that machine than what you could possibly save in elictricity bills.

Yeah, I guess. As I said above RTX3090 was even unplugged. I may have to try out the Windows desktop separately too but the reason why I wanted a dedicated desktop was for using a triple monitor setup and none of the MacBooks I own can do that yet.

And I should've been clear. This minimum of 200w happens in both Mac OS and Windows. So I am suspecting this is mainly from the CPU because that watts is outputting even when idle.

dominicperry said:

The 16-core version with the Radeon 580 idles at about 90w under MacOS and 70w under Windows. Windows seems to be better at clocking down to lower levels when there is nothing going on.
But it's a big Xeon chip, it will never be like a new M1 - my MBP 16" 10/32 with 64GB runs at 6w idle.

Dominic

That is interesting. Let me double-check again with W5700X also. I definitely did notice though that having 2 cards did that really matter as one or both cards do not even run when idle. So for me, this is a CPU-reliant issue and the only way I was asking here was to see if I can maybe disable some cores as I might not even need 12 cores when idle (so maybe down it to 4 or 6 cores or maybe even constantly doing that to see if I see a decrease in power consumption).

So when it's asleep it drains exactly 17w. With just one monitor when it runs it actually drains about 60w more (from 260~270w to 200w), so I guess outputting 2 additional monitors also draw some power. So overall it is definitely on par (single monitor) as per Apple's website. All in all, I wish there was a way I can lower the core from 12 cores to say 4 cores on Mac OS. Is there one?

In Windows, I've tried just lowering the processor state from 0~100% to 0~30% and I did notice about 50w loss, and from 30% down to 20% and 10% the difference is way more visible than from 100 to 30%, so I thought putting it at 30% was the sweet spot for everyday usage (web browsing, etc.).

I hope this helps.

Yikes. I can only imagine what my 5,1 is doing to my power bill...

LEOMODE said:

That is interesting. Let me double-check again with W5700X also. I definitely did notice though that having 2 cards did that really matter as one or both cards do not even run when idle. So for me, this is a CPU-reliant issue and the only way I was asking here was to see if I can maybe disable some cores as I might not even need 12 cores when idle (so maybe down it to 4 or 6 cores or maybe even constantly doing that to see if I see a decrease in power consumption).

Try using CPUSetter and see if that works still. If it does you can disable how many cores you want to.

shardey said:

Try using CPUSetter and see if that works still. If it does you can disable how many cores you want to.

Thanks! I will definitely try it out with Mac OS. Do you know any Windows equivalent app?

I tried CPU Setter under MacOS 12.6.1 and it made no difference to idle or low-activity power consumption whatsoever, even going down to a single core.