This the new build

msi 790xt-g45

8 gbs of 1066 ram
an amd 1055t
1tb hdd seagate
nvidia geforce dual 250
antec neo eco 620c

my problem is i can get the power supply to turn on i push the button and it lites up for a second and then nothing i have tried making sure the positives and negatives were right to my question is there anyway that the cpu can keep the power supply rom starting up

please im stuck here and the is a cable i dont have a slto for the 1394 cable could that be the problem thanks for you help in advance