RE: Alienware X51 R2 formatting hard drive
Why Win 7? Some games require Games for Windows, which have issues under Win 10.
But I would not think so because isn't "Game for Windows" a Microsoft creation? Win-10 Compatibility Mode should take care of all that. However, older games might not be fully patched ... that's up to developers.
Glad to hear you got it going, and are satisfied with end-result. 
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