Power Not Working

Question

I just got the vizio 42 inch tv i plugged it in and for a minute and a half it worked then it went off. There is no power at all not even the name display in the front , no standby either. I called Vizio and they told me that it may be a power supply problem but they were not very helpfull. I wanted to know what i could do to try and solve this problem .If that means opening the back of the LCD so be it but i am not sure what to look for i can not find any specs for this tv that show me what to do . I have tried different plugs and cords but nothing works.I hope to hear from you soon thanks