late last year I wanted a bit more room for C drive having a 840 pro 256 after deleting games all the time to make room for new ones. choices -buy a new 500gb ssd - evo's looked cheap or a 850 pro. -use my 750gb evo back up drive and back up to what ,had it with spinners. -new ssd in 2015 should be cheaper \ better, but did not want to wait. -plus only intel 2 sata 3 ports so looking around I found another 840 pro on sale cheap , so back to raid 0 I go. seems it was the right move for now.