ubuntu14.04双显卡解决方案，本人亲测，完美解决

Install Nvidia-Prime in Ubuntu 13.10 or 14.04

 

Follow the instructions below only if you know what you’re doing and how to revert the changes in case LightDM fails to start, etc.!

Update: the instructions below should work under Ubuntu 14.04 Trusty Tahr too.
Note: the  nvidia-prime package only supports the proprietary Nvidia drivers and won’t work with Nouveau!
If you’re using Ubuntu 13.10 Saucy Salamander or 14.04 Trusty Tahr and want to test the Optimus support in the Nvidia Graphics Drivers 319.12+, here’s what you need to do:

1. Firstly, purge Bumblebee if installed:

sudo apt-get purge bumblebee*

Also, make sure
libvdpau-va-gl1 is not enabled system-wide because it causes Nvidia Settings to crash on start – if it is, either disable it or simply remove the package:

sudo apt-get purge libvdpau-va-gl1

2. Install the proprietary Nvidia drivers and the Nvidia Prime package:

sudo apt-get install nvidia-319 nvidia-settings-319 nvidia-prime

[/code]

Install Prime Indicator in Ubuntu

 

Prime Indicator is available for Ubuntu 14.04 Trusty Tahr users in the main WebUpd8 PPA.
To add the PPA and install it, use the commands below:

sudo add-apt-repository ppa:nilarimogard/webupd8

sudo apt-get update

sudo apt-get install prime-indicator

sudo reboot

原文链接：http://ylxfc.sinaapp.com