Monitor not turning on

So recently I decided to swap in between cases since I needed bigger one for more decent cooling and additional parts that I wanted to add/swap. Ever since switching over my screen does not turn on.
I have a
AMD Fx 8350 Eight core CPU
MSi 760 GMA p34 motherboard
8 GB Ram
500 GB HDD
950 W Power supply
Hp 2011 20 inch monitor
Radeon HD 6870

The case that I decided to get myself is
V8 Black Gaming Full ATX Tower PC Case USB 3.0 Red LED Fans Clear Side Window
in order to fit in my new hydro H80i GT as well as my new graphics card that is coming on 12/08/2015 which is GTX 960

after transferring all of my components over as well as mounting my new H80i GT cooling I attempted to turn my PC on
Fans started working as well as lights for PC and other components turned on.
However the screen stayed black
I did not get any display on screen
The only indicator I get is that monitor is currently plugged in to power
whenever I press any button on the actual monitor it says that "VGA/DVI" cables are not connected.
Which is not the case, I'm not sure whenever it is faulty motherboard/GPU or monitor (no clue what is causing this at all).
I will be able to perform tests on different GPU this wednesday but if anyone can help me out I would be greatful.