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Microsoft tells Windows 10 users to just trade in their PC for a newer one, because how hard can it be?
(www.xda-developers.com)
This is a most excellent place for technology news and articles.
I'd just be scared of windows trying to clobber my nix partition.
Use separate disks.
Personally, I've never had trouble even with partitions, but Windows isn't going to mess with drives that aren't NTFS.