im new to all this mining thing, i bought a sapphire dual x 280x but im having a couple of problems.
first of all im using cgminer 3.7.2 cgminer.exe -I 14 -g 2 -w 256 --thread-concurrency 8192 -o stratum+tcp://stratum-us.doge.hashfaster.com:3339 -O username.worker:pass
but im getting only rejects. 100% rejects.
secondly, my hashrate is only 613~ i read that this card can have 730~.
plz help me

if anyone have skype/teamviewer that would be great!
10,000 doge prize to who will solve this problem