Black screen on Start up Cant install OSX
Hey guys, I have a Mac pro 2008.
When i press the power button the white light shows up then the scheme and then all i have is a black screen. NO apple logo NO grey screen nothing.
then in a few seconds Windows 7 Loads up.
I tried to insert Mountain lion cd i hear it working but i cant see nothing the screen just wont turn on.
I tried different screens tried different video cards different cables.
I tried replacing Hard drives.
the problem is that WINDOWS 7 boots and works great but i cant install OSX in any way.
please help.