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[miketworld929]

Will I need or use a software update such as the long overdue Denim update if I plan on using the Windows 10 preview available this month?

 

[Athull]

You can directly upgrade irrespective of current software/firmware. Check this thread.
http://forums.windowscentral.com/windows-10/339263-how-does-wps-update-system-work.html