a new gameing rig

[Croninberg]

hi all need some help with a new gameing pc, is it best to go 6 core I7 or 4 core I5? i would like my new pc to last without upgrading to much maybe only sli the graphics card at a later date 780ti or 970, need os, ssd and large hdd needs to be built for me as im not confident to build one. have about £1500 to spend. have monitor already. have been looking at titan storm you sell very nice rig. any help is appreciated thanks

 

[Croninberg]

i do need an os have mouse and keyboard, 1080p monitor but will upgrade to get 4k when price drops, does the gtx 780ti and 970 have similar benchmarks as single cards and does either of them beat the other when you sli them?