Every one you get like that will do that, those SUCK! One 12 volt rail @ 17amp.
Send it back and buy a quality brand one. You can not buy a quality PSU 480watts for $30 anywhere.
SHould cost around $70
Try Antec TruePower or Fortron.
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And the sign says "You got to have a membership card to get inside" Huh
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