Hmmm. My experience with XPS 15s is you can turn it off with software in Linux, but it was pretty technical (not something average users would be keen on). I wasn't sure if that was the case for most laptops. It definitely wasn't drawing 0W when I was just coding/browsing/etc though, it doubled the battery life in Linux when I turned it off.
Yeah, my experience with iGPU+dGPU setups outside of MacBooks has been messy. Part of the problem perhaps is the various different ways it can be set up, e.g. with/without mux switch, and last I knew AMD and Nvidia handle iGPU ↔ dGPU handoffs differently rather than agreeing on a standard.
With that in mind I'd also prefer that there be a way to flip off the dGPU in BIOS to guarantee that it can't unexpectedly become a power vampire.
I don’t think apple gets enough credit for how good their automatic graphics switching implementation was. I’d argue that most users who benefitted from it didn’t even know it was happening. It’s such a useful feature too, because dGPUs generally kill notebook batteries, and even at idle, they probably generate an impactful amount of heat.
Is there truly no equivalent to apples automatic graphic switching for PC laptops? If so that’s WILD.
AMD and NVidia now use the same standard, which is PRIME for handoff and automatic shutdown using Runtime PM, and if needed muxes are handled by the vga-switcheroo.
On the latest NVidia/AMD hardware, no configuration should be required, unless you try to use Wayland on NVidia.
Unfortunately on NVidia you really need the latest hardware, both on the GPU and CPU side. If you do, it should generally "just work". Of course Linux is Linux and it might not.
It depends on how recent the motherboard and GPU is, if you have an NVidia dGPU. If you have a GPU made in the last two years and a recent CPU, it works automatically out of the box with X11. On older systems, it's pretty technical, but thankfully many distributions now come with tools that handle it all for you and give you a button you can click to turn it off.
ASUS laptops, as of 6.1, I think, have kernel support and a userspace CLI and GUI to trivially configure this stuff (`asusctl`). In Windows, you can use GHelper and avoid the hundreds of megabytes of gaudy crap that is Armory Crate to configure this as well.
`asusctl` (the CLI), and `rog-control-center` (the GUI) lets you configure fan curves, "ultimate mode" (mux switch), LED lights, effects, panel overdrive, battery charge limit and more
And then `supergfxctl`, when "ultimate mode" is disabled, allows you to configure "Hybrid" or "Integrated"(-only) graphics modes.
For completeness/disclosure, flipping the mux switch aka Ultimate mode on/off) requires reboot, though it seems this may become unnecessary with new/future hybrid graphics tech in laptops.
ASUS should shower the developer in money, this G14 2022, all AMD is the most satisfying, best, complete out of box Linux experience I've ever had. And I've owned a lot of Lenovos, Dells, etc.
