280x > 270 > 270 > 270
Mind to share your 280x config? Which 280x you using? Also Windows and AMD driver version..
The sgminer is that the version you downloaded from first post?
Sapphire 280X w/ Stilt BIOS Dual-X Windows 8.1 x64, 14.6 Drivers @ 1150 mV using TRIXX. My card is subborn so that's why it's only hashing at that rate. And yes I think I'm using sgminer version from the first post, I don't remember
First values are the 280x
"intensity" : "18,17,17,17",
"thread-concurrency" : "8192,6401,6401,6401",
"lookup-gap" : "2",
"gpu-threads" : "2",
"worksize" : "256,128,128,128",
"expiry" : "1",
"queue" : "1",
"gpu-engine" : "1120,1120,1120,1110",
"gpu-memclock" : "1500,1500,1500,1500",