"So i built my pc i5 2500k with a gigabyte z68xp ud3p and seasonic x 650w psu. My pc starts up and the leds on the mobo turn on, all fans spin, and a few seconds later it turns off and then restarts again. Can anyone tell me what is going on? I dont get anything on my screen or any sounds."
In my opinion, it is most likely an issue with your power supply. It could have a problem, and I don't know how trustworthy of a brand Seasonic is because I've never heard of them. Go for a reliable and well known brand for power supplies like Antec or Corsair. Antec's 620 watt power supply is $59.99 (USD), the Antec NEO ECO 620C 620W. It can also be brought down to $39.99 with a rebate.
http://www.newegg.com/Product/Product.aspx?Item=N82E16817371031
Overall my guess is that your power supply is faulty, or doesn't actually supply 650W of power, maybe 300-400W. Try a new power supply or test it on a different pc.