Display Port only working after HDMI is plugged in

[livelyosprey]

So I didnt know what category to put this in so here goes

PC was fine until it just black screened and turned off. I thought it could be a GPU problem or something but the HDMI had an output.The display port still showed no output.

However, when both the HDMI and the display port were plugged in you could remove the HDMI and the display port will work. How can i fix this so that I can start my PC without the need of the HDMI?

 

[PuperHacker]

Please do check here: http://www.tomshardware.co.uk/answers/id-3314182/displayport-quit-working-switching-hdmi-day.html and here: http://www.tomsguide.com/answers/id-3608846/displayport-hdmi-works-connected.html