HD 6770 flashed to HD 5770 Black Screen

[slc2015]

Hi,
I flashed my AMD Radeon HD 6770 to an HD 5770 Device ID, keeping my Subvendor ID as ASUS. When I go to install Lion, whether I boot in verbose or normal mode, the screen always goes black after the Apple logo. How can I fix this?
Thanks,
Sam

 

[iUserosx]

Which port ur using ? VGA or DVI ? For single display u must use the DVI port .......if u dont have a DVI connect in monitor try using a DVI2VGA adapter.......it should work........I've got success with an XFX card the same way..