You may want to try ScanSetup (attached) and set all parameters to zero.
Make sure MyHD is not running when you change the parameters, or they won't work.
Let us know is this helped.
> ScanSetup.exe can control the overscan or the underscan of MDP120 but it
> works with the driver version 22.214.171.124 or later.
> If you set all the parameters to zero on ScanSetup, any overscan or
> underscan will not appear on the output of MDP120. If you'd like the video
> to be overscaned or underscaned, set the corresponding parameters in
> ScanSetup to the desired values. The overscan values and underscan values
> can be set at the same time. For example if you use 16,16,16,16 for the
> underscan and overscan, this will result in clearing the edge of the video
> with the background value without any overscan or underscan.
> Please note that the horizontal parameters must be a multiple of 16.
> If you have any problem with it, please mail me.
scansetup.zip 6.947265625k . file