would I get more than 15 mh stock setting on win 7 850 power supply try 3 different miner software it hook up to tv but using on board graft known if that could the problem my nvidia rig has no problem have not used amd since the 280x . I was using older broad gen 3 pci. no riser
this is really simple to answer. Win7 is no longer a good option for you to use.
So if you only have the one pc and want to run win 7 on it you will get the low hash.
Do you have a second pc?