On my computer i have 3 hardrives. One full of games @500GB one with the computer @1TB and contains windows 8.1/recovery and other partitions. My last one which i recently received from a friend, @320GB and the one currently booting up with my system. Even tho in BIOS its set to use my 1TB one it still boots here, which is not a problem. except it has windows 8 illegally i think. my computer always asks for an activation key, my wonder is can i use the one from my other HDD with windows 8.1? Assuming i upgrade to 8.1 soon? because i'd rather use this 320GB HDD for my windows installation, and everything else on different HDD. possible? or not?