Can I keep my OS when I upgrade my mobo, cpu and ram?

[Qub]

I currently have a pre-built that came with windows 8 (I'm using 8.1 now) and an AMD a8-5500 processor and some mobo I don't know the name of. I will be upgrading to an i5-6400 and a MSI B150 Mortar Arctic soon and would like to know if this upgrade will require a new purchase of Windows or if i can still use the copy that cam with the prebuilt (I'm pretty sure I have all the needed info about the key). If i can still use the same Win 8, then what will I need to do to prepare the HDD to work with the new hardware?

 

[Dark Lord of Tech]

That windows OEM key is tied to the prebuilt.

 

[Qub]

I've heard that oem's are tied to the mobo, so if the os is an oem, does that mean I couldn't use the same copy of windows?

 

[Dark Lord of Tech]

That license is tied to the prebuilt.