The computer CPU has the core graphics card, the independent graphics card is Nvidia's GeForce. There is usually a priority when installing Fedora 20 64-bit. There is a boot option for the video card in the PC BIOS, PCIe or Igfx,pcie is a standalone graphics card, and the IGFX is an integrated Intel Core display. Do two experiments.
1. Set the BIOS display to PCIe and disable the use of the kernel. When the monitor VGA is plugged in, a discrete video card is launched at startup, but the screen is not lit because the standalone video card is not connected to the monitor. Until the start is complete, enter the system, you will actively recognize the nuclear display, the monitor correctly connected.
2. The BIOS setting is the same, the monitor VGA is connected to a single display, then everything is OK when booting.
3. The BIOS is set to IGFX, the monitor VGA is connected to the nucleus display, everything is OK.
4. The BIOS setting is not changed, the monitor VGA is connected to the display, and the boot is normal. The Fedora system is not displaying properly.
The above situation can be represented by a table:
----------------------------------------------------------
VGA IGFX | VGA PCIe
----------------------------------------------------------
BIOS IGFX display starts normally, system does not display
---------------------------------------------------------
BIOS PCIe System not displaying properly
---------------------------------------------------------
It can be seen that Fedora 20 is not good for dual graphics support. If the use is unique, then the boot is set to PCIe in the BIOS, and the VGA is connected to PCIe by disabling the display. If you use the IGFX,VGA, the BIOS boot entry is set to the interface on the motherboard.
Dual Graphics installation Fedora 20