To turn off a computer, you have to go to shutdown menu, you can't disconnect it directly from the electric power source(desktop computer), otherwise, if you are not lucky, you will get your data lost, corrupt in file, or even computer will not work at all.
Many things are different between Windows 7 and Windows 8, one is the way to shutdown the computer.
To Shutdown Windows 8
• Move your mouse cursor to the upper right corner, or you can use Windows(logo)+C (on the keyboard), then will appear the menu at the right side.
• Choose the Setting logo
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