Vauxus :
Jonas Magnusson :
Windows 8(or 8.1) takes less RAM memory to work, but it's a very new kind of style which many don't like.
Windows 7 is the "classic" windows version in it's last version(maybe windows 10 will be more like windows 7).
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For gaming i choose both, why? because all the games i have work fine in windows 7. but windows 8 don't support all of them(for example: Driver San Fransisco) .
Windows 10 is looking a lot better than 8. It has the Windows Button, and the lower tab where your programs are located.
https://www.youtube.com/watch?v=84NI5fjTfpQ
Cool thing is that the start menu has basically all the apps you want on there. Looks a bit odd to me, but of course it'll take time to get used to.
I agree that windows 10 looks better, but don't use it for gaming...yet. Because it doesn't have any good or official drivers yet since it's beta/preview.
Windows xp/7/8 are the best for gaming. Windows xp can run the games optimally but windows 7 can run almost every game out there. Windows 8/8.1 is the newest one and takes less resources than windows 7/vista and has the latest drivers on the market.
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If you really want to use windows 10, wait for the official one in 2015.