Three of my computers have Nvidia GeForce GT Optimus cards:
None of three laptops allows to switch Nvidia OFF from BIOS.
Three cards aren't the same as yours, but anyway. I never use Nvidia and always run on Intel GPU. Like you, I want to exclude Nvidia from being used.
Below are steps I use to completely exclude Nvidia from being used in Solus. Some are simple, other are complicated. I won't describe steps in details.
Never install nvidia drivers.
Add modprobe.blacklist=nouveau to boot params. Don't confuse it with nomodoset= param. It's a very common error. Do not use nomodoset=. Use modprobe.blacklist=nouveau.
Uninstall nouveau video driver.
Install and configure by hand bbswitch only, without Nvidia drivers. Configuring bbswitch is not a trivial task, but it is described in the forum. Search for it. This assures that bbswitch runs only once, on startup. It may be not enough. So I go further, to the next step:
Schedule periodic bbswitch execution for switching Nvidia OFF with systemd. I switch Nvidia OFF with bbswitch once a minute. The main goal here it to switch off Nvidia cooling fans off, which may periodically enter in action, even though dGPU is not in use.
This is not a trivial task either. I didn't see it described in the forum or elsewhere.
Install tlp, and run it on startup in battery saving mode. Create a .desktop file to launch tlp, if neccessary (Gnome 3). Tlp is present in Solus repo.
Install thermald. Enable its service once with systemd, it will run on its own forever. Lowering overall system's temperature reduces the need in spinning cooling fans, thus saving the energy. Thermald is in the repo as well.
From all the above, bbswitch is the most important tool. It contributes the most in "killing" Nvidia.
