New
#11
You should be fine as far as activation, AFAIK CPU isn't a 'major' change as far as activation is concerned.
Any problems with activation with the new CPU just right click the start orb, click run, type slui in the box and press enter, choose yes on the UAC pop up, then on the next box that pops up enter the license key from your copy of Win 8.
I had to do that when I changed my MB, used the key from my Win7 Home retail version that I did the free upgrade from. It activated immediately with no problems.