ICS on w8.1 slow speeds

Hi, sorry if this is a bad place to ask, since this is more of a network problem but anyway, I noticed my download speeds on devices connected through my main rig's ICS(internet connection sharing) are terrible, I have a 10mb connection and it always starts at 4-5mb and then plummets to near 0kbps



the setup is like this= main router/wifi connected to main pc through WIFI then main PC shares the internet through windows' ICS that goes to a secondary router/wifi using utp cable, then the secondary router connects to the rest of devices using WIFI



problem is, the end devices never get full download internet speeds, upload speed seems to be ok, what is weird is I can transfer files locally from main pc to end devices using the exact same connection at full speed, and whats weirder is if I connect one of the end devices to the secondary router using utp cable instead of wifi, it gets full speed for internet like it should



I guess the secondary router's wifi is not the problem since it works normally unless the data is coming from windows' ICS, but it works just fine when using Ethernet whether transferring files locally or using internet through ICS



then what may be the problem here? I guess ICS is adding more protocol overhead and since Ethernet is faster, wifi just collapses with the amount of data?



btw I tried with different wifi channels and using another computer as main pc and got the same results



anyway thanks in advance for any help ;)

ICS on w8.1 slow speeds