With a 270x I'm getting very poor performance. gpu:0:Hawaii [Radeon R9 200 series]. In the work queue the ETA on the gpu is 10 days while my cpu is about 2 and a half hours. Any suggestions? Is my card just not powerful enough for this type of work?
Make sure to leave one CPU core for the GPU. Can you post the first lines of your log file with system info and config ? Also what driver versions is important. But i can't help with AMD, I'm a NV guy.