Using kernel 3.18.0-1.gfc82a91-default (note that all other kernel versions I
tried resulted in same issue)

On Lenovo G50 laptops with Realtek wifi (pci 10ec:b723) There is an issue where
the max wireless speed in an excellent wireless environment with AC1750ac/n
enabled is limited to less than 5 mbits/s
There is an available driver set for rtl wifi from: 
https://github.com/lwfinger/rtlwifi_new
that should be looked at for future updates. 
My experince has been that installing the code there boosted my wifi to 66
mbits/s
All tests were run using iperf bewtween two OpenSuse 13.x machines (13.1 wired
ethernet and 13.2 wireless).