So I have had this machine for a few years. Suddenly it turned off when I was using it. It keeps turning on for random amounts of time and then completely shuts off and repeats. Sometimes, it gets to the desktop for a while and other times it turns off and on within a few seconds. I have tried removing and switching both ram slots, removing the GPU and cleaning everything. Also disabled Automatic shutdown when something goes wrong. When it is on long enough to even get to the bios, the CPU and memory temps are only around 30°C. I have switched out the hard drive as well as reset the CMOS jumper. The external PSU brick has a constant green light on it so I am not sure if it is the PSU or not? Can anyone help? The warranty has expired.