I just got a gigabyte r9 380x. I'm getting like 120 fps in CS GO... i was getting 150 -170 on my r7 260x. same setting. same computer.
a10 6800k 4.5ghz, gigabyte f2a68hm-h motherboard, 8gh crucial 1600 ram, 1T HD, 600 watt power, windows 10 pro, cooling, all that jazz...
I uninstalled my old drivers before installing the r9 380x
after i saw the frames i was getting i uninstalled the r9 380x and its drivers then reinstalled it just to be sure... no change.