Lets say I want to build my own system, can I buy Windows 10 OEM and use it legally?
I know that Windows 8 OEM introduced this allowance, but 8.1 OEM got rid of it.
So, what's the score with Win10 OEM?
Windows system builder licensing for personal use
Build a custom system for me and I will buy it from you for $1. Then I will sell it back to you for $5. We both win.
It's the same as for 8.1.
Windows licensing and packaging
(The System Builder license is intended only for systems intended for resale. Further, Win 10 is supposed to be set up with a particular out of box experience, where the OS is installed, but the buyer sets it up on first use.)
As far as I know, there is no enforcement of this.
I have only purchased a System Builder license once (for Win 7). I didn't use the OPK to install it, and I didn't sell the system. (I built it to give to a friend.) It has been in use for years.
I can't encourage someone to break an end user license agreement, but if you did, your risk would be about zero.
Whether or not it is better to go for the Retail version depends really on how often you update your system.
Personally I'd always go with retail as I change my mobo and CPU every few years.
Alright, so in theory one can just buy Windows 8 OEM (since Win8 is cool with system builders), and then upgrade to Windows 10 before end of July, right?
Okay, so now the question is, for Windows 8 OEM, what constitutes a "system builder"?
Do I have to buy every PC part individually and build it myself?
Or can I buy a 99% complete PC (without the OS of course), and then simply install a sound card for example to qualify as a "system builder".
In order to qualify as a system builder you must assemble at least 100 computers per year from individual components. No, I'm just kidding! I wouldn't worry at all about how many components you have to assemble to be a system builder. I don't think Microsoft defines that anywhere. To me, the last step of building a computer system is to install the OS and make sure it all works.
Well, I admire your efforts to keep everything 100% absolutely legal. Personally, though, I would just purchase a full retail of Windows 10 and not have to worry about transferring it to an upgraded computer in the next few decades. That's what I already have planned to do for the next custom computer I build for myself after July 29. I just built mine about 2 months ago, but I had a retail Windows 7 that I could install on it and then upgrade to Windows 10. That retail Windows 7 was a family 3 pack license that I purchased in 2009 and it's been on so many computers over the years that Microsoft won't activate it online any longer and I have to call them to activate it. But, as of two months ago, it's still going strong. That license is the basis for the 3 non-OEM Windows 10 I have on three computers at my house. It's just one product key for the three licenses and apparently Microsoft does not differentiate between the single install and the family 3 pack product keys for Windows 7.
Windows 7 Family Pack | eBay
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