I'm currently running a 16" connected to a Cinema display. This always triggers the high performance graphics card (dGPU).
I've disconnected the charge cable, so running on battery - but still connected to the external display.
Running pmset -c gpuswitch 0
has *no* affect on the graphics card setting; still running the dGPU.
Activity monitor's saying that there's 2h45 left on the battery. There are no applications using the graphics card. The highest CPU is Firefox staying around 10%. Literally as I am typing this paragraph it's dropped to 2h36.
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I'm struggling to trust this 16" for client visits. As we have to have all the damn "special" power supplies, I've two; one in each office. Disconnecting those is a bloody nuisance as they're under the desk. So I'd like to be able to trust the 16" machine to do a half day out without going flat on me.
I've yet to see the 16" get to within 50% of their claimed 10 hours. I feel this is a politician's promise.
Now down to 2h29
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Question: how can I disable the dGPU for all modes? (As sudo pmset -a gpuswitch 0
doesn't seem to work)
I've no use for the dGPU for my normal workflows - office work, browsing, listening to music, development using VMWare Fusion. I don't run games nor video editing, etc.
Ah, the problem with dedicated cards on 15" and 16" machines!!!
You cannot run external monitors without triggering the dedicated GPU. That kills battery life and elevates the power consumption and temperatures.
That is a design choice from Apple and the reason I struggle with the 13 vs 15 decision for years. I love the added screen real estate, but my needs don't require a dedicated GPU.
I currently have 15 2018 i7 AMD 560 pro. Temperatures on office work range from 32C to 44C on iGPU, while running dGPU with external monitor it ramps up to 60-65. Solution was to ramp up fans to minimum of 2500 and use active cooler base to keep temperatures below 50C. (PECI sensor)
External monitor battery times go around 2h30 to 3h, while using iGPU gets close to 8:30, sometimes 9. These machines never get more than 3:30 with external monitor connected. It has always been like this since they created double GPU back in 2011. Battery times always measured with Integrated GPU.
Maybe they decide along the way to take advantage of new Intel integrated chips in 2020, who knows?
But as it stands we have to live with what we've got. Thunderbolt connections are tied to dGPU.
I would like to buy new 16" machine next year but I need the new machine to have these issues sorted, by using the iGPU or a really efficient dGPU that does not kill my battery and gives me the opportunity to fry an egg on it just because I want to use a fullHD external display with it...