recently built up a PC I'm still planning to upgrade, GTX650, i5-4590s, 4GB DDR3. according to many websites this rig needs like a 250w power supply to run but before properly checking it, I bought a 500w PSU from a local store. long story short the PC doesn't turn on, when everything is wired up and I press the power on button, all fans start up for like half a second and then instantly stop, nothing else, although it works just fine with a 420w PSU from my old PC. is it possible than the load on the 500w PSU is too little for it to function? I'm sure it's not a connection problem, I've checked on them and re-wired everything many times, it still doesn't work.