I broke my friends new computer
Why would you break his new computer?
I ran out of patience for him
I admit that I have destroyed some things in the past because of my anger and my lack of patience, but those things that I have broken are my own and not other people stuff. Breaking your friends computer on purpose is a very bad thing for you to do and you need to replace it. I suggest you also talk with your friend to discuss with him why you are always running out of patience with him.
Me breaking the computer is his fault.
It sounds like it's your fault and I think you should ask for forgiveness, then replace the computer.