Phoronix: GPU Switching Goes For The Gold: Mainline Inclusion

At the start of the month we talked about GPU switching coming to Linux in a crude form that allowed notebooks with dual GPUs (one being a low-power, low-performance integrated chip and the other being the more performance-oriented GPU that's power hungry) to be switched from without the need for a reboot in Linux. This initial work was just a collection of hacks by David Airlie and it required VT switching after killing the X Server, etc...

http://www.phoronix.com/vr.php?view=ODAxOA