I`ve currently got an i5-8400 and a gtx 1060 6gb in my phanteks evloo ITX build, which is my first ever. Only tampering ive ever done with it is installing a m2 ssd, which took me wayyy too long. At the moment im planning on getting the new Assassins creed, which im not entirely sure itll run at high quality. Should i upgrade the cpu or the gpu, if any of them?