I have a AMD 5470 card in my HTPC. I'm using HDMI out from the HTPC to my Marantz SR7005 receiver. The receiver is using HDMI out to my Sony HW50 projector.
The Marantz SR7005 receiver has an OSD (On-Screen-Display) feature that cause sound level and other stuff to show up on the screen.
For this to work, the receiver has to be set to convert the video format. This has been working fine with windows 8.1.
After installing Windows 10 preview I noticed that the OSD were no longer working. However, if I installed the AMD driver it got back and would work.
Every time that Windows 10 was updated I had to reinstall the driver.
What I figured out was that this was caused by the Pixel Format. With Windows 10 only my receiver (Marants SR7005) did not recognice the pixel format, and I assume that because of this the receiver was not able to convert it and thus not able to display the OSD menu (as displaying the OSD meny actually means modifying the picture before showing it on the screen)
I assumed that this was due to Windows 10 issues.
However, with the lastest AMD Driver (15.7) just updating the driver no longer solved the problem. Now I have to go into Catalyst Control Center and change the Pixel Format to RGB (full) for the OSD to work.
From what I can understand there seems to have been done some changes to the Pixel Format for the YCbCr 4:4:4 format causing the receiver to longer understand this pixel format.
I will assume that the changes was first introduced in the drivers delivered with Windows 10 and then introduced into the 15.7 version of the driver.
In the receiver the Pixel Format will just be shown as "..." when using YCbCr 4:4:4. Before, after installing the AMD driver, it would show up as "YCbCr 4:4:4" - indicating that something have changed with the way the driver gives information about this format.