Another aspect we found irritating with Intel's GPU control panel is the custom resolution section. Intel seems very reliant on EDID and doesn't allow the user to input any frequency not supported by the display. Our testbed display (a Sony Bravia KDL46EX720) doesn't indicate PAL compatibility in its EDID information. I was able to play back PAL videos with matched refresh rates using the Vision 3D (NVIDIA GT 425M) as well as the AMD 7750. However, Intel's control panel wouldn't allow me to set up 50 Hz as the display refresh rate.
Discrete HTPC GPUs are necessary only if one has plans to upgrade to 4K in the near term. Otherwise, the Ivy Bridge platform has everything that a HTPC user would ever need.
Thanks for the links.... got one for the HD 2500?
(Oh, and a bit of topic... What the ---- happened to MoD? Now would be a good time for a renaissance...)