Sudden DVI issues #GPU

I have a dual boot system that has been working with no issues for some time. I have Mac 10.8.4 and Windows 7.







I havent installed anything new nor changed anything in my hardware but today i experienced what started as screen flickering then developed into black screens and then into a total loss of connection where the screen when a fuzzy grey.







I tried a restart but it was the same on both windows and OSX.







I then removed the DVI cable and tried with HDMI instead and Windows booted with no issues except my bios screen and boot menu had a black border around them , as did Windows but i fixed that by setting overscan to 0%.







I tried booting OSX but all I got was a black screen like OSX didnt like HDMI!







So right now im confined to Windows....which i hate!







So my questions here are:-







1) What is at fault here ? The monitor or Graphics card? The monitor still has warranty but I dont think the graphics card does sadly.



2) How can i use OSX with HDMI?







Any help and advice would be very very much appreciated!







System info:-



GA-Z77MX-D3H



Gigabyte Radeon HD 6850 1GB OC



i5-2500k without HD 3000



8gb Corsair ram



Dual booting osx Mountain Lion with Windows 7