Disable Intel graphics for Optimus systems (e.g. E6420)

Is there anyway to completely disable the intel graphics in system that has the Optimus technology that switches between the intel and discrete graphics?

The optimus switching is not working, and even when I force an application to run with nvidia, it does not seem like it is working properly...

 

you can disable optimus in bios

 

Are you using drivers from Dell or directly from nVidia/Intel?

Mine seems to be working just fine with the stock Dell ones.

 

TL;DR:
Nope. Even if you disabled optimus you would end up stuck with the Intel GPU. Your only choices are Intel or Optimus switching.


Longer answer:
Optimus works by routing graphics calls between the IGP and the dGPU. Typically the Intel IGP is the only chip that's hooked up to display outputs, with the Nvidia GPU hooked up only to the IGP. There is no way to directly use the GPU for graphics purposes without routing it through the IGP, and the only way to do that is through the Optimus driver. If you disabled the Intel IGP you'd end up with nothing. If you can't figure out a solution through the Optimus driver, then chances are you're out of luck.

Does this mean there is no solution? Of course not, but some very smart Linux developers have been trying to figure this out for a while now so I wouldn't hold your breath.

 

Nope. On Dell systems at least, if you disable Optimus in the BIOS, it will use the discrete GPU only. With Optimus enabled it works as you described; however, there are connections from both the Intel GPU and the discrete GPU to the display with a mux so it is able to bypass the Intel GPU if you turn Optimus off.

 

oxygen is correct
You can disable the Optimus feature, to run only the Nvidia NVS 4200M.

Optimus is used to keep the Intel 3000HD active for power saving reason, when intensive GPU load such as games will be rerouted to the GPU (usually automatically with Nvidia Control Panel). You should only install Dell Intel and Nvidia drivers from the support section for the best compatibility (yes they are out dated) but I didn't recall any problems with the Optimus feature.

 

Good to know. This is definitely good news from Dell if they have hardware muxes. You wouldn't happen to know which Dell laptops carry muxes would you?