I worked on a Meridien system that had the 3D board go bad.  It looked exactly like what you posted.

I don't know if this works on a Symphony Meridien, but hold F and X on the keyboard when you fire up the software.  Choose to disable the 3D board.  Render.  If the problem goes away, it's likely the board.  If it's still there, it will be obviously that I probably don't know what I'm talking about.

Michael.

Black bar is ony on one side. We rented another system and took out our hardrive and used the rental sytem and the problem persists. Maybe cabling. Again you only get the effect on rendered media. Tried to go to local and fibre storage and both had the problem. Any thoughts

Replace your 3D board.

JDS