I notice auto adjusting brightness i.e. brightness keeps varying based on background contrast on the LCD screen when I use HDMI out from my Gigabyte 880GM USB 3 Mobo. It has ATI Radeon Onboard Graphics 4250
As such this happens only on HDMI out and not on VGA.
My OS is Win XP 32 bit SP3

Moreover the Dynamic contrast option is unchecked (disabled) on both the LCD TV settings as well at ATI’s CCC Application. I wonder what is causing this.
It’s a new mobo and this is noticed from day1. Am not very familiar with advanced graphics options, could there be any more settings to adjust or may be this seems to be some issue with HDMI? Thx.