Keeping all my other parts, GPU, HDD, PSU - just swapping out the board (my sabertooth or FX took a dump on me, haven't figured it out yet but when I get one or the other working again I'm putting them in a test bench)
basically is there anything on the software side, in windows that I'll need to take care of once I got the new board/cpu on?
You will need to re-install Windows. The driver set in your existing installation will likely not make it past the initial loading screen. Then, as Z1Only points out, Windows will see it as a new PC and demand to be activated again. If it was a Retail version, it may succeed, but if OEM, it won't. I too have explained the death of a motherboard to Microsquishy, and been allowed to reactivate an existing copy. Chances are, their system indicated that I'd bought numerous copies of Windows over the years, and was therefor not likely to be a pirate. I cannot speak to the results you will get, but I think I'd be optimistic.