What Would You Do ??

What do you want them to do? If their diagnostics don't return anything of interest and you are unable to reproduce the problem, I dont' see how you can complain about the service.

If I had to guess, it's probably the power outlet you're using or there is a loose connection somewhere. Try using a different outlet and plugging all of your cables in firmly.

 

When you got it back home from the store, plugged it in, what happened? Has the problem persisted?

 

You "finally got it to power on". How? What did you do differently?

 

Have you filmed this? I mean if you film someone pressing the power button (make sure the click can be heard) and then just film the output I'd have thought that was enough evidence.

 

I know this doesn't help, but I think the error you made was not asking for a replacement within your 14 days return period. You would have had no problem getting one.

However, I can bet that if you call Applecare and complain you will get a replacement.

 

Came here to say this. But on a second read, the wording makes it seem as if the OP just received the iMac and has been having problems in the last couple of days.

Clarification on that? Have you had the iMac for 3 weeks or was part of that shipping time?

 

just return it, can you take it to the store?

 

Like others have said document it by recording it. Every bit of it including plugging it into the wall. You could also plug something else into the wall to demonstrate that its not the sockets issue. Show it to apple and they should replace it.

 

why don't you just exchange it? You only received it for a few days right? If they say nothings wrong and won't exchange it for you, just return it and repurchase...