I just lost the analog video on an HD5850. No telling when it first went out as it seemed to be working fine, and is still working perfectly, crunching GPU tasks. I only noticed the problem when I did some GPU board shuffleing and it ended up being the primary monitor. It works fine when connected to an HDMI, DP or DVI monitor. I don't have any DP or DVI monitors, but I used adapters to an HDMI TV to verify the video was working.

I suspect it would be cheaper to buy a DVI monitor than to send the board in to HISDigital to get the analog video fixed. It had been 4 days since I asked their support about repair fee and they have not answered.

I bought two adapters on amazon for nvidia boards some time ago. Later, nvidia drivers changed behavior and those plugs were not needed. At some point I remember putting it on the ATI board and I must have left it on there which seems to have been a bad idea. The plug did allow me to bring up the catalitic (?) control panel to make a change, but I should have pulled the plug off afterwards. Their control panel wont show performance tools unless the plug (or a monitor) is connected.