Windows 7 x64 was the most popular OS on Steam last month
 

Recent numbers from Microsoft suggest almost half of all Windows 7 users run the 64-bit version. When it comes to gamers, though, the x64 flavor looks to be even more popular. So shows Valve's Steam Hardware Survey for July 2010, which pegs Windows 7 x64's usage share at 30.32%—higher than any other operating system in the list, including Windows XP x86

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