iMac 27" - Black screen

[Sazaj]

Hello everyone,
(I also want to mention thag I'm a newb with iMacs)

I have a problem. My iMac 27" mid2011 screen is completly black - its not turning on.

So what have I done before my problem, was to clean the formed "dust" that was on that white panel and that see-through panel. Now everything is connected, but the screen wount turn on.. I can hear the chime sound and the fans working after I press the power button.

I would be glad if anyone could help me fix this.
Regards,
Sam.

 

[Sazaj]

I would also like to attach this video -

- from the minute 5:00 to 6:30, my dad and I did not place the screen horizontally, but vertically. The main see-through panel went out (we could see 5 or so green connectors I think). Could this cause my iMac not to display anything after start-up? Is this fixable? Or do I need to buy a new screen?

 

[Sazaj]

FIXED!!! Forgot to plug in the cables in the LCD panel