is my amd fx 4130 black edition (4.1Ghz) bottlenecking my amd sapphire r7 260x



An increase in maximum FPS/video quality. Your CPU will still dictate minimum FPS dips in the game engine. It might be worthwhile to see if there is a used r7 260x on ebay for ~$50, but I wouldn't invest more than that, since saving for one single better GPU would still be better in the long run.