Windows 7 x64, AMD R9 280x 3Gb cards, i downloaded additional tahiti kernel, getting:
...
Ok, got it working but just after I renamed tahiti_144.bin into tahiti.bin.
Damn you are right ^^ Well you see some stuff written / released here with a hot needle. Well ... thats why its a preview ^^
Fiji speed avg. 14 S/s too slow.

use little power, I think it user more power, speed is up.
For NVIDIA algo 144,5 use more power is the same 200,9
wait tuning for AMD....GO GO GO

I will start tuning for AMD asap - right now lets sort out the AMD driver troubles

A little more info - R9 280x 3GB not overclocked (1000/1500MHz) with Crimson 15.12 drivers, Windows 2008 R2 x64 (or Win 7 x64 SP1 codebase, don't ask me why I run server version
), getting between 6-8 sol/s per card.