R6700v3 will only output 20Mbps instead of 200Mbps

[4H_Dad]

I Recently upgraded from 20 Mbps to 200 Mbps with my internet service. If line is hooked from modem to computer directly, 200 Mbps is achieved. If hooked to R6700 router, then a line to the computer, only 20 Mbps. Latest firmware is uploaded. 

Cable guy was here and ran tests and said something is wrong with the R6700v3, maybe how it's setup. I did a restart on the router and redownloaded software, but still the same. Any suggestions would be greatly appreciated!

[plemans]

Did you try factory resetting the router? 

During the reinstall, don't use a backup.