Please share me config for 270 and 280x.
270 run 1mh it right ?
280x all HW

I use the following config for my 270s which gives about 1.35MH/s per card.
/bin/sgminer --kernel jackpotcoin -o stratum+tcp://jpc.hashatme.com:3333 -u user.1 -p x -I 19 -g 2 -s 1 --temp-cutoff 90 --gpu-engine 1140 --gpu-memclock 1500 --gpu-powertune 20
Your 280X's should produce about 2.5MH/s.