PCIe card not recognized by System Profiler

MacPro3,1
OS X 10.6.8
BMD Desktop Video 9.5.3
Multibridge Pro

I've tried 3 different Multibridge Pro PCIe cards in slots 2,3, and 4 in my MacPro.

None work.

DesktopVideo shows "No Settings Required", greyed out settings.

System Profiler shows only Video card (ATI Radeon HD 2600), no BMD PCIe card.

I was told this system worked before Adobe CS6 was installed... possibly on OS X Leopard... but now now cards are recognized.

Any suggestions?

I've seen several other posts about similar situations with Resolve, but not with the Multibridge.

The system worked with FCP 7 and Leopard last fall, I've been told. Then it was upgraded to Snow Leopard and PremierePro CS6 installed (by someone else.) Now the DesktopVideo control panel says "No Settings Required" and the settings are all greyed out.

I've stuck with DesktopVideo v9.5.3 as that's the last one compatible with Snow Leopard. I tried older versions (after uninstalling previous version) but they didn't help, so I reverted to 9.5.3.

I have three different BMD Multibridge Pro PCIe cards (there were originally 3 separate editing systems here.)
I have tried:
Each card in PCIe slots 2,3, and 4
Two different DVI connectors (both original BMD cables)
Three different Multibridge Pro breakout boxes.

I have also tried the three PCIe cards in two other Mac Pro towers of similar vintage.

Many different configs, NONE of which allowed the PCIe card(s) to be seen by the CPU.

Is it possible for three cards to go bad? Or is it a software compatibility issue?

I've emailed BMD Support too, but no response.

I admit, I'm trying to avoid completely wiping the computer and starting from scratch if possible.
Any suggestions, short of "start over"?

I don't mean to bump this thread excessively, but I've received no response from several emails to BMD support (not even acknowledgement or a promise of a followup), and can't find any documentation online to help solve my questions.

Is this a software compatibility issue? Or could THREE Black Magic cards all go bad? Is it shoddy manufacturing? Has anyone else had a similar experience? How'd you fix it?

Anyone?

I would think by now someone from BMD would have responded to this thread. I would think by now one of my support requests would have received a response.

But I'll keep trying here, and through BMD support channels, and hopefully I'll get some answers.

Hello Tangerine,

I double checked with our support team and they can't seem to find the email you registered on the forums with in our files here. I would suggest emailing them again.

tech@blackmagicdesign.com
or contact them @ (408) 954-0500

"tech@blackmagicdesign.com
An error occurred while trying to deliver this message to the recipient's e-mail address. Microsoft Exchange will not try to redeliver this message for you. Please try resending this message, or provide the following diagnostic text to your system administrator."

I guess I'll try calling on Monday.

Thanks Tony!