Please answer all questions fully:
what is your graphics card output resolution?
what is your graphics card output refresh rate?
(ie to the LCD / projectors)
what frame rate is catalyst set to?
what is your SDI input resolution?
(ie SDI signal to the Phoenix card)
480i / 480p / 576i / 576p / 720p / 1080i / 1080p
what is your SDI input frame rate?
23.98 / 24 / 25 / 29.97 / 30 / 50 / 59.94/ 60Hz?
How many inputs are you using?
Any other PCIe cards installed?
is the SDI input De-interlaced?
Try disconnecting the SDI inputs
then disconnect the output of the graphics card and re-connect
Then re-connect the SDI inputs one by one.
Does this make a difference?
S