If you are sure of the video card, you seem to be left with the inconvenient truth that a poor connection, either physical or logical, is at work. Is the video cable to the display known-good? Is the video-out connector clean and bright? Is the brightness control of the monitor (if there is a physical control) at minimum? Is the display working? Is the display compatible with the Radeon? Is the Radeon software on the drive(s)? (Yes. Even without it you should get something.)

As the man-on-the-spot you are infinitely more able to check and recheck every rational or irrational possibility, all the while hoping that it is not something unexpected and overlooked that is having effect. Your problem is unusual, especially with a 9600, but even something as way out as having no ground connection in your mains cable could play a part. Best of luck, and keep us posted.

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