On the ram it should say what the voltage is.
Some boards need it bumped up a notch with 2 or more sticks.
What ram is it, and what is the rated voltage?
Give us some detailed specs on this rig please.
Make, model# of, memory, motherboard, PSU, CPU, video card.
Can you try 2 sticks at once in another computer?
Did you put the stock cooler on?
That maybe the short, not showing up out of the case.
Maybe shorting stick to stick, then to case when installed?
Worth a try at this point.
And yes you will need a receipt to RMA it.