I have a brand new Toshiba Satellite L850 with i7 3rd generation processor 6 GB of Ram and 750 GB HDD and AMD RADEON 2GB graphic card with 2 ports of USB 3.0. The problem is whenever i try to copy files from my external WD USB 3.0 HDD the system slows down and i can't even open google chrome page or play a video until the transfer finish. I almost tried everything. For example I updated my BIOS ,restored the laptop to factory state .... etc. when I uninstalled (intel usb 3.0 extensible host controller) everything running smoothly but the speed of USB 3.0 ports decreased to USB 2.0 speed. If I install it back everything returns as before.
Please Help.