Folks on here are correct. Recommended psu is 400-450 at least. You haven't given us the card model or if any of your components are oc'ed. Your cpu is a 95 watt part, plus the other components, stock. Its it an oc card? I guess it really doesn't matter tough. It is a 99% chance that it is your psu. They age and lose the abilities they once had and your power requirements have gone up. It works after a reboot because it cools down. Seasonic 600 watt or better is a solid choice and can be had for a fair price. There are others, Antec, EVGA, etc. that have good reputations. Look at the end user reviews on any model, at any price range you choose. Please put your 260x back in until you get a sufficient psu so that you don't lose everything. Good luck and God bless.