Today tip will help
you to display the hidden devices in system Device Manger. Normally
windows device manager displays the information about the hardware that
ever been recognized by windows, whether it is currently present in the
computer or not connected to the computer (for example USB or any other
removable devices). The "Show hidden devices" option on View menu
would not display the all hidden information, so you can force your
system to display the detail of all hidden drives.
Follow the given steps to display the all hidden information in
device manager:
To edit the computer registry, first you should log onto your
computer with administrative rights.
Click Start button and type CMD in Run option
then press Enter for next.
At the command prompt, type the following command and press Enter
button.
set
devmgr_show_nonpresent_devices=1
Here again type the following command at command prompt and then
press Enter button.
start devmgmt.msc
Now in the Device Manager Console go to
View
menu and select the "Show hidden devices" option.
Now expand the different devices and drivers option in devices manger
and you will find the devices which have been loaded in the past.
When
you finish troubleshooting, close Device Manager and also exit from
command prompt to clear the opened sessions. 
COMPUTER TIPS