I have managed to fix this by upgrading my kernal to 4.5.0 :)
I have moved from windows to Ubuntu recently and I have installed Ubuntu 16.04 on my new Dell xps 15 9550 laptop. Everything works perfect except the display. It keeps flickering. maybe the problem is with the NVIDIA graphics.  Will someone be able to help me with this issue. Thanks [IMAGE]
[XPS 15 9550]Display keeps flickering after upgrading to Ubuntu 16.04