--shaders 1792? The R9 280x has 2048 shaders. Any particular reason you're not using all of them?
Honestly, i don't know what the shaders are for. I just copied that part on my config from 7950 cards. i will try to use that and i will post here the effect.
Also you use -l 1 I believe this to be log which is by default set to 5.
cgminer thread says "--log|-l Interval in seconds between log output (default: 5)" but i don't really understand it. why do you have it as 1?
