Upgraded to kernel 4.2 but getting black screen after that

I had a mainline kernel 4.2.5 and based on the advise that i should not have a baseline kernel as in this thread I installed it via this command

sudo apt-get install --install-recommends linux-generic-lts-wily xserver-xorg-core-lts-wily xserver-xorg-lts-wily xserver-xorg-video-all-lts-wily xserver-xorg-input-all-lts-wily libwayland-egl1-mesa-lts-wily

but after that i keep on getting black screen. I thought it's because of my nvidia driver so i referred my earlier thread

and then executed

sudo apt-get purge nvidia*  
sudo reboot


sudo add-apt-repository ppa:graphics-drivers/ppa
sudo apt-get update
sudo apt-get install nvidia-361 nvidia-prime
sudo reboot 

But i am still having black screen. Even if i do

Highlight the Ubuntu menu entry and press the E key. Add nouveau.modeset=0 to the end of the linux line. Press F10 to boot the Ubuntu operating system

I get black screen only.

Had a chat with Pilot6 execute this command

sudo apt-get install linux-generic-lts-wily xserver-xorg-lts-wily libgl1-mesa-glx-lts-wily libglapi-mesa-lts-wily libgl1-mesa-glx-lts-wily:i386 libglapi-mesa-lts-wily:i386

lspci -k | grep -EA2 'VGA|3D'

tells that nvidia kernel is in use

Later i purged nvidia and install it

sudo apt-get purge nvidia*  
sudo reboot

sudo add-apt-repository ppa:graphics-drivers/ppa 
sudo apt-get update 
sudo apt-get install nvidia-352 nvidia-prime 
sudo reboot

But even after that I am having black screen only. I need to login into Recovery mode and then normal boot and then Ctrl+Alt+F1 to do any work.

============================================================================== Very unstable system - it was working for around 10-15 minutes then mouse and keyboard - everything is un responsive.

I curse my self - why i tried to do mess up something which was working alright. Even if that was mainline kernel it was working fine.