Reading further into your message - Just to clarify in case you are asking something slightly different -- you don't have
to install Windows 7 to remove Windows 8. But, you do have to install Windows 7 if you want to go back to Windows 7 from Windows 8. If that makes sense?
In other words, you can remove Windows 8, but no, you can't revert back to Windows 7 once you've put Windows 8 on without reinstalling Windows 7.
Your message taken literally would imply if you wanted to install Linux or something you would have to install Windows 7 and then install Linux
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