Question Windows 10 Upgrade - from a Windows 7 machine - Does my father need 'Retail' or OEM ok?

Jason3022

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Apr 16, 2012
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Do I need to purchase Windows 10 Home Retail or OEM copie(s) for the following scenario?:

My father has 2 computers - 1 desktop, 1 netbook:
They both have Windows 7 installed.
Desktop: I was going to install Windows 10 on a new SSD I will purchase.
Netbook: I was going to format existing drive and install Windows 10 fresh.

How many Windows 10 versions will I need, or is Retail good for multiple? So many conflicting thoughts online.

thanks
Jason
 

Jason3022

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Apr 16, 2012
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Ok, thanks.
I just came across this information online, which is what confused me.
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OEM versions of Windows are identical to Full License Retail versions except for the following:
  • OEM versions do not offer any free Microsoft direct support from Microsoft support personnel
  • OEM licenses are tied to the very first computer you install and activate it on
  • OEM versions allow all hardware upgrades except for an upgrade to a different model motherboard
- OEM versions cannot be used to directly upgrade from an older Windows operating system
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That bolded part confuses me; if I buy new OEM versions, doesn't this mean I can't upgrade the 2 computers that already have Windows 7 on them? Or am I misunderstanding that?