Is it possible to do clean Windows 10 install over an older 2009 iMac?

The iMac is an early 2009 model that does support Bootcamp for Window 7 (8?). Early 2009 iMac's cannot upgrade to the latest Sierra OS X because of hardware so it occurred to me, why not upgrade the iMac to a fresh install of Windows 10. Can this be done?

I believe the problem lies in the iMac's motherboard as Windows drivers are not installed (BIOS). Even if I install Bootcamp drivers to the MB directly, I still could not install Window 10 because 2009 iMac's will only go up to Windows 7 or 8 & I don't think Microsoft is supporting 7 anymore either so we'd be right back to where we are now.

Anyway, is it possible to do clean Windows 10 install over an older 2009 iMac?

NavyLCDR said:

Microsoft is scheduled to support Windows 7 SP1 until January 14, 2020:
https://support.microsoft.com/en-us/...cle-fact-sheet
But, I don't know if 2009 iMac will support Windows 10 or not.

Thanks. That would work fine. No need to clean install, just use the Bootcamp feature & purchase Windows 7. And, my iMac will not support Windows 10, just Win7 32bit.

The whole reason for my question was I had the impression that Apple was discontinuing support for this iMac's OS X 10.10.5. Apparently Apple will support it for at least another year.