USB left port loses connection

Hello, i have an Alieware 15 R4 and when i plug some external HD the speed is very slow and then loses connection... but the right usb port works perfect. Even if the left port was 2.0 i think the connection would work... 

Ps: I found another topic similar here, but is the 17 version.

Anyone had the same issue, or solution? All my drivers are up to date too...

Thanks!