How to use dedicated video card instead of onboard?

I figured it out.

I had to toggle my prepared graphics processor from the Nvidia control panel (pretty weird), and then it worked just fine. A reboot was required.

This setting only exists for Nvidia Mobile ("M") series graphics cards.

Just in case anyone else reading this is a massive idiot like me, one other way to prioritise a dedicated GPU over an onboard one, without having to worry about fiddling about with your BIOS etc, is to plug your monitor into the socket on the dedicated GPU rather than the one on the onboard graphics card.

Only took about an hour of mucking about with settings for me to spot that one!

Check your BIOS.

You need to either:

• Disable the on-board graphics, possibly by disabling any shared graphics memory (or setting allocation to automatic).

Or

• Set the primary adapter to be the dedicated card, PCI-e x16 or similar (BIOS dependant).