To force video level expansion for SD you have to add the "UseBT601CSC"="1" registry key for the Catalyst display driver. Are you using the ATI DVI -> HDMI dongle?
Regards,
grubi.
problem solved.
I had an Ati 2600 PRO (dismissed) and now a 3850. there is 2 entry in registry 0000 and 0001. the last one 0001 is related to 3850
Device Description=ATI Radeon HD 3800 Series
this node DO not had UseBT601CSC!!
Italy