windows 7 - Vga on new monitor not working with rig

Have built a new rig and got new monitor...

Here's the specs of the rig:

http://pastebin.com/4B6gBpRk

Basically the monitor has one hdmi and one vga input at the back. I know the vga input on the monitor works because it works when I connect a laptop to it. However, when i try to use my gtx680 as the source (dvi to vga adapter) the monitor just shows a black screen.

I know the vga cable works and the dvi adapter does too as I can hook the rig up to my tv and it works over vga no problem.

Any ideas what I can do? I need to use vga not hdmi as I cannot access the UEFI over hdmi.

Thanks for help, I need to find out quite fast only have 4 days left to return the monitor if it is somehow incompatible with my computer.