Black screen on death on both GPU cards. HELP!

[gogul1]

Black screen after installing old GPU again.
I have installed a GTX 680 (pc) in my mac pro 3.1
I then installed a PCIe ssd into the 2nd slot.
I then put the old radeon 2600 back into slot 3.
It was alll working great. I could swap via both DVI ports on both cards and got a picture. In order to test the GTx 680 I then removed the old radeon GPU and it still worked fine. Was working on installing win 7.
But in order to install win 7 via bootcamp I put the radeon card back in so I could choose a partition to boot from if need be.
Now I don't get a picture from either. Initially I plugged the DVI into the back of the radeon and all i got was a grey screen with a flashing folder and a question mark inside it.
I the changed the DVI lead to go into the GTX 680 to see if that helped but it was just a blavk screen.
Any ideas? Pretty sure it was working fine yesterday but today it is behaving bad (

 

[m4v3r1ck]

Black screen after installing old GPU again.
I have installed a GTX 680 (pc) in my mac pro 3.1
I then installed a PCIe ssd into the 2nd slot.
I then put the old radeon 2600 back into slot 3.
It was alll working great. I could swap via both DVI ports on both cards and got a picture. In order to test the GTx 680 I then removed the old radeon GPU and it still worked fine. Was working on installing win 7.
But in order to install win 7 via bootcamp I put the radeon card back in so I could choose a partition to boot from if need be.
Now I don't get a picture from either. Initially I plugged the DVI into the back of the radeon and all i got was a grey screen with a flashing folder and a question mark inside it.
I the changed the DVI lead to go into the GTX 680 to see if that helped but it was just a blavk screen.
Any ideas? Pretty sure it was working fine yesterday but today it is behaving bad (

I advice you to keep all trials-and-errors for your installation in the same thread. So others members have a better overview on what you have done so far!

 

[gogul1]

OK had to plug in a wired keyboard as the apple wireless one won't work fast enough to allow me to press the ALT button down. Selected my boot drive and it works again.

Curious as to why I need to use a wired keyboard. What if ai want to switch between OS? Do I need to pull out a wired keyboard EVERYTIME?!

Anyway I digress. I want to install win7 on bootcamp so want to be able to boot with the radeon and use the GTX 680 for gaming. Is that possible?

Also not sure the radeon in very good for resolution and wanted to use GTX mostly.