New system built last weekend and when I turn the power on after 10 to 15 seconds the system shuts down. Everything looks like going to start fine, but just shuts down to quickly.
Motherboard Asus P8P67 Deluxe B3 Revision
RAM G.Skill RipJawsX DDR3-1600 PC3-12800 4MBx2
CPU Intel i7 2600
GPU EVGA Nvidia GeForce GTX580
PSU Antec 550 Watt BP550 Plus
HD Western Digital 1T WD1002FAEX
Case Nine Hundred Two
250w is only 25amps so I would try running your system first. As long as you use 6/8 pin connections from different rails you should be fine. I would try it before you buy a new one. If you want to know if it will work all the time, try running Furmark. It runs your GPU at maximum, so you will know if it works.