i have a 2 month old i7 iMac. Today I moved my router across the house and the iMac is now using wifi instead of being plugged in. I have an ac1200 router that works great and my other devices can max out my 90mbit internet connection in the same room as the iMac. The iMac will only get max 60mbit, and usually less than that. I've tried resetting pram and SMC but nothing seems to work. I've had macs for 20 years and I'm stumped. the only thing I can think is that possibly one of the internal antennas is not connected. Any ideas?