i8cookiemonster
Distinguished
Looks like you guys may have stumbled across an X-Box 1 dev kit card last year and not even realized it! It's clocked at 860 MHz so the shipping version probably won't vary much from that (I'd even speculate lower due to maximizing yields, etc). Not sure about the RAM though, it might be possible but I wouldn't hold my breath...more likely they'd work on optimizing the OS to decrease it's memory footprint.
http://www.tomshardware.com/news/Pitcairn-radeon-HD-7850-768-shaders-gpu,15524.html
http://www.tomshardware.com/news/Pitcairn-radeon-HD-7850-768-shaders-gpu,15524.html