The card worked fine until after a Windows Update last year.I don't know which one it was.
When I went to the support page I only found ATI Radeon HD 4850 X2 drivers. I installed them and I when I attempt to stream to my TV by HDMI the image is great, but there is no sound.
Windows Troubleshooter didn't help. When I test the connection I receive an error message.I have attached a screen shot.
I have Windows 10 Pro 64 bit on a desktop PC