I am running the 32bit Win8 Preview and it works but thankfully I saved the former user data on the drive from a Win7 installation because Boinc will NOT install. It is unable to create the Boinc_Users Group account. But since I saved the User Data I was able to find the Boinc installation on it and Boinc is now crunching for Moo using an AMD4670 gpu.
Here is the pc:
http://moowrap.net/show_host_detail.php?hostid=4071

As for the Win8 Preview it is designed for a tablet or a touch screen environment but the mouse works fine. It has 'app' buttons like a smartphone! It has a Windows Explorer button, all are a single click, that takes you to a traditional Windows7 desktop screen so everything is still there, that is just not the default screen anymore. The Win8 Preview on the Moo Webpage says: Microsoft
x86 Edition, (06.02.8102.00)

While a regular Win7 says:
Microsoft Windows 7
Ultimate x86 Edition, Service Pack 1, (06.01.7601.00)

Oh you can download the Windows 8 Preview at:
http://msdn.microsoft.com/en-us/windows/home/

BUT it is NOT designed for a regular working pc, it takes over your pc and I don't see a 'go back' button, so either use a different hard drive or a spare pc, NOT one you use for anything else! I build my own pc's so have some spares and it is running on one of those. ALL units run on this pc have been thru Win8.

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