Can I pack a box (like Fed Ex box) and check it in on an airplane as my luggage?

I'm going to Vietnam in a few months and I'm planning to bring a few of my computers. I plan to pack them in large brown shipping boxes and I was wondering if I am going to be allowed to check them in as my additional baggage. I know I will have to pay an additional fee and adhere to the weight restrictions, but I just would like to know whether it was possible or not. Also, do you think I would run into any trouble with customs when I arrive?