Pozdrav Branko,
It works. I use
http://bsod.pw pool for Galactrum (largest hashrate). Use this way:
mkxminer.exe -o stratum+tcp://pool.bsod.pw:1982 -u wallet_address -p c=ORE -I 20 --asm
Watch your intensity for temperature and power draw. One of my 280x is overheating when used with intensity 21, others are working ok.