There is still problem with switchable GPUs: namely those, where one GPU is using Mesa and the other is not (i.e. Nvidia). Those computers didn't disappear for the face of the Earth, people are still using it and expect it to work, even if there are never laptops available on the market. It is being worked on (https://blogs.gnome.org/uraeus/2016/11/01/discrete-graphics-...).
Intel doesn't supports GPU switching on its MESA drivers it requires the proprietary one.
Get the prop nvidia and intel drivers and get nvidia prime and you are golden.
Same issue with AMD GPUs with intel CPUs especially the PowerXpress ones.
They do have a binary firmware, for Broxton and newer, however that's a thing that runs on the GPU. It does not have anything with how Mesa or other OpenGL stack shares buffers and video output devices.
Do you have a source for this? In any case, just because some hardware has been recently phased out doesn't mean the manufacturer shouldn't be expected to support it. Not everyone has enough money to buy a new computer every year; I'm a student with an Optimus laptop and I know I won't be able to afford a replacement in the next year or two.
If NVIDIA can't be asked to fully support their hardware on Linux, the least they can do is release some documentation so the Nouveau devs don't need to grope in the dark.
I don't disagree in principle, but they've killed it, releasing information to make it work might be a problem for them, and since this thing is no longer supported adding compatibility for older devices isn't a high priority for them.
It worked poorly on many windows machine, it's effectively still doesn't work on Windows 10 [0] and it's been effectively killed since 2014.
[0]https://forums.geforce.com/default/topic/860554/geforce-mobi...
It's also worth noting that NVIDIA couldn't get the darn thing to work on Linux, it's also worth noting that AMD also had/has similar issues with PowerXpress on non-Iris based Intel CPUs, it does somewhat work well on AMD's own CPU's with integrated graphics and it's more modern "APUs".
>Do you have a source for this?
Source for what? under Iris Intel the CPU handles the switching between GPUs not that it works that well, but it doesn't work well on most OSs other than windows mostly due to how the display driver infrastructure is setup and how the composition manager works (even on OSX you still likely to want to use gpu-switch than rely on the OS).
If you want to blame some one blame the OS tbh, if OSX and Linux had proper user mode display drivers like WDDM, had modern display drivers like WDDM and actually had a composition manager capable of using multiple GPUs then there might be better solutions for this.
But overall it works, it does require you to use the proprietary drivers from both NVIDIA and Intel but it works, at least on Ubuntu I never had issues with following a similar guide to this http://ubuntuhandbook.org/index.php/2016/04/switch-intel-nvi... (reading the comments on that guide it seems that it missing an important part which is apt-get install nvidia-prime) So this just works...
To switch between the 2 on demand you can simply use these commands:
-prime-select intel
-prime-select nvidia
On other distros (or if you are not using nvidia-prime) you might need to use /proc/acpi/bbswitch And modprobe/rmmod to do the switching, there are bash scripts online ready to use which are available as long as you have the proper drivers installed.
P.S. Sorta OT but relevant: http://i.imgur.com/Ql1dsZC.jpg
Also it looks like PRIME supports synchronization now if you have a distro with DRM support (no not the bad kind ;) https://devtalk.nvidia.com/default/topic/957814/prime-and-pr... so if you are using their currently suggested setup you don't need to switch manually anymore.
This is much more expensive than hardware implementation of Nvidia Optimus.
It's more expensive on Linux because the DRM on Linux is broken, there is no longer "Optimus" since NVIDIA no longer uses a dedicated chip, you share a frame buffer with the IGP.
PRIME also supports the older Optimus chip laptops, but again this doesn't work that well, but then again these don't work well with Windows 10 either due to the changes to WDDM.
