DISABLING OF ON-BOARDD GRAPHICS

[AsusP7H55]

I have a computer with a P7H55-M motherboard with on-board graphics. I just bought a Radeon HD6670 graphics card for HD gaming and video. When I install this, the computer fails to start. The manual that comes with radeon graphics card recommends disabling the on-board graphics before installing the card. How does one go about disabling the on-board graphics ?

 

[refillable]

Boot through your Onboard Graphics and go to the BIOS. There you should find that option.

 

[AsusP7H55]

I tried this, but there no options in BIOS for disabling. I thought there could be some other way