Windforce 3x model GV-R928xOC-3GD
It's been mining exp for the last few months, gettting 26-27Mh with ethminer-nr (my fork of Genoil's miner).
https://github.com/nerdralph/ethminer-nr/tree/110I'm focusing on development with the AMDGPU-Pro drivers, which don't support the 280x (and other GCN 1.0 cards), so I'm selling it.
US$85 or C$115 + shipping costs from Halifax, Canada. I'll throw in a ribbon riser for free.