In July 2019 I heard from Oleksandr who was using his S900 as a media centre running OpenELEC along with the Yatse app on his Android phone. He had used a standard right-angled PCI riser to add an Asus Xonar DG sound card to provide a Dolby 5.1 digital output.
He reports that the S900 "...is able to play 20 gigs full hd bd rips...as well as some online video from 3rd party web sites" .
Any comments? email me. Added July 2019