I would recommend to just simply to get a new PC altogether. If that's not an option i would recommend using older version of chrome or use Firefox, since latest version of Chrome seems to heavy for your computer.
so you gonna OC 4790K and 2x1080 ? i 850W-900W PSU, dont forget to get Tier 1/2, and just to make sure the 80+ doesnt mean it has 80W extra, its just an efficiency rate