when I connect my phone( android device) and Ipad to the computer, it works but after 1 second it stops the connecting. After that, it connects again and stops in 1 second.So the cycle to repeat.(in other computer, same usb cable, same devices, it can work） But it is no problem when i connect the portable Hard Disk to the computer.
After i uninstall the K1100M drive, it was fixed. But once i install the K1100M drive, the USB port can not work again when i connect the phone to the computer. I have tried all the version of the K1100M drive and still no solution.
i confirm the problem does exist.but it is not necessary uninstall nvidia driver, would be enough just disable K1100 in device manager and usb ports starts working as they should. why Dell can't solve this problem in such expensive laptop i don't understand