NVIDIA-Redhat 7.5

Hi Guys,

Need urgent help!
I tried installing Nvidia 390.87 in my HP-elite(intel core i7,Geforce GTX 1080). After installing the drivers I am getting blank screen. I also contacted Nvidia support, they hinted me to use init3 before installation and init5 after installation of drivers.

So init5 is giving me this now:
PolicyKit daemon disconnected from the bus.
We are no longer a registered authentication agent.

Can you please help me with this. I am a newbie with Red-hat

Thanks
Prem Rao