Verdell good answer.
You probably won't get best buy to reply to this but what Khalil says sounds right to me. The geek squad could take a look but if it isn't a typical psu then they would probably send it somewhere.
Depends on if it is internal or external. Most lower supply cords can be purchased, but if it's internal, it will most likely have to be returned to manufacturer.
If not they would have the replacement you need.
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