I do not know the specifics but a large issue with the 5 is that a lot of hardware acceleration for encoding and decoding video was removed, making it slower for anything to do with video.

This too.

You can only stream 720p out at 20 FPS from my 2711 though, so it only seems to decode well = watching/consuming media. (the future is producing)

The 2712 can stream out 720p at 40 FPS. (CPU)

The 3588 can stream out 720p at 60+ FPS. (CPU)

Edit: HL2 runs at the "same" FPS on each (sometimes 300+ on 3588)...

Ah, yes, it's definitely a poor choice for most video-encoding and some video-decoding use-cases. Just not sure how GP goes from that to "dud"...