(note: For this tweak, you will need a free utility called nircmd down loadable here)

1. Right click on your desktop, choose new > shortcut.

2. Paste the following:

nircmd.exe qboxcom "Do you want to Shutdown?" "question" exitwin poweroff

3. Click next, call it "poweroff" (without quotes) Click finish.

4. Now, right click on the shortcut you just made, choose properties. On the shortcut tab under shortcut key, type whatever you want the keyboard shortcut to be e.g. ctrl shift p. Click apply, ok.