I am using Dell Insipiron 7567.
I have dual booted my rig with Ubuntu 18.04 and Windows 10.

Right from the start itself I couldn't get to the screen of trying or installing with default settings. I had to use 'nomodeset' with 'quiet splash'.

Even after installing I had problems. After some hours of searching I found out that installing Nvidia 390 driver would remove the bug. It did. But my rig heats like shit. And throttles very much. Where as I am not using anything other than
1.chrome
2.vscode
3.terminal

Which i think is very normal?
And looor of battery drain.

I used to get around 3-5 hrs of battery life in Ubuntu Gnome 16.04 but now its like max 2 hrs.
Which is bad I guess.

I switched back to "X.Org X server" driver with "nomodeset" (without nomoseset it will load upto login page. Once i hit enter it gets stuck) it boots up but can't change the level of brighness or can't do anything related to display setting. Temperature has reduced but sacrificing on display settings.

Is there any way to remove this bug?

And additional infos

Graphics in about shows something like "llvmpipe (LMVM 6.0, 256bits)"

Guys do respond please?