Remove Unused Drivers and Devices

My Computer / right click / Properties / Advanced / Environment Variables /

Below the bottom Environment Variables window pane (System Variables), click on New. Enter for “Variable Name”:

“DEVMGR_SHOW_NONPRESENT_DEVICES”

and for “Variable Value” enter 1

Then My computer / right click / manage

right click Device Manager, click on View and then select Show hidden devices from the menu. You can identify the hidden devices by their grayed-out icons and remove them.

If you remove a piece of hardware without first uninstalling it in Device Manager, the drivers remains behind, but the device no longer shows up in Device Manager by default. By removing unused driver your system speed will not increase, but it is good for cleaning and may lower conflicts with new drivers, and may also prevent possible system errors.