I find it difficult to believe that you can get a device that'd have problems playing back a Netflix stream. Even Intel integrated graphics can scale a 720p stream to 1080 without issues, unless you use a pixel shader-based upscaling algorithm.
The mid-range laptop I am currently typing on has trouble displaying video fluidly at times which is most likely due to it's lack of a dedicated video card.
My desktop which is running the exact same operating system and core programs plays video much more fluidly, and it has a dedicated (still extremely weak and outdated) video card.
add windows and .net and silverlight and DRM monitoring in the stream app and bogus graphic card drivers and other concurrent programs fighting for bandwidth on the same machine such as torrents with the awful bandwidth scheduler of said windows, and you have your answer somewhere.
