Originally Posted by spivonious
That's outdated information. Since Silverlight 3, it has had full DXVA support on Vista and Windows 7. Only XP still has partial support but you can't blame Microsoft for not putting in too much effort on a 10 year-old OS. The quote from that thread is from a random developer on the Silverlight forum, not from Microsoft.
That was for Silverlight 4 and I'd like to see a document from Microsoft stating that it supports DXVA per se and not just GPU hardware acceleration as those are two different things. You can have GPU hardware acceleration (e.g. for resize, etc) but still have the CPU doing all the decoding. I've actually read through some of Microsoft's white papers and I've found none that specifically mentioned Silverlight supports DXVA.
From what I've noticed with the way Silverlight works, video engine load is near zero while most of the load is on 3D (!). Try playing a Netflix HD stream (in browser) and monitor GPU load with GPU-Z and see what you get. Pressing Ctrl+Alt+Shift+M in the Netflix window during playback should bring up a menu and you can select A/V Stats to monitor the Netflix stream (bitrate, frames rendered/dropped, etc) as well as CPU usage.
I don't know if the issue with DXVA not being supported is related to Silverlight itself or just the Netflix implementation. Either way, the outcome is the same - for now, an Atom still won't do for Netflix HD.