I think I saw messages here about the successful launch of srb on v8 on pitcairn, but I could not find it. Install recommended driver first and then try to use the settings that are in this message for tahiti.
Radeon R9 270X 4Gb (Pitcairn) with manual modded bios, Windows 10 x64 Pro, 18.10.1 driver. Gives 500 h/s on v8 with kernel 1, with kernel 2 speed slower.
Owners of 580 8Gb please share your settings and wich kernel file you're use?