Try with this one
sgminer --gpu-platform=1 -o stratum+tcp://pool.hashbag.cc:8644 -o -p c=SIGT
you may need to use gpu platform 0,1,2 depending on which openCL platforms you have installed, you can find a list of those in Regedit at LOCAL_MACHINE/Software/Khronos/OpenCL/Vendors
if you look there you should see the amdocl64.dll listed (if you are running a 32 bit miner on a 64 bit platform then you need to look inside HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Khronos\OpenCL\Vendors)
remove the intel one (write down the value that was in there in case you want to restore intel openCL) that's in that folder and reboot your machine and then you should only have the amd platform left and sgminer won't get so confused
I have try with all --gpu-platform but doesn't work !
anyone is able to work with AMD RX GPU ?
what miner u use ?
You may need to remove the intel openCL platform from those registry keys and reboot - my RX gpu works fine with sgminer