My PSU can handle the r9 290. I'm tired of people typing that. That's why it's hard to pinpoint problems. Everyone believes it's the PSU, but in reality it's something else. If I listed my PSU, the only thing you all will recommend me to do is to buy a new PSU that has more wattage. I've done stress-testing with both my CPU + GPU at the same time, while at full load, yet my system never turns off. It mainly turns off when I'm trying to play games, or watching a youtube video at 1440p(sometimes it does, sometimes it doesn't.)