Sounds like the power supply to me as well. You may want to open the case clean it out with air get all the dust and dirt out of the fans the gpu and the cpu and heatsinks after that try again. If you still have the problem remove your cpu heatsink clean old thermal paste off put new on a pea size drop and reattach the heatsink. Then try to run if that don't fix it check your power cable to the back of the pc make sure its snug and if that don't work it may be time for a new power supply.