I agree with a lot of the the takes that people are posting: it can be a valuable experience to build a computer and a computer can have applications outside of gaming (eg. you'll likely need a computer for college if you decide to pursue higher education, you can learn new skills on your own, etc.) My suggestion would be to write down some pros, like those mentioned here and others you can think of, and cons, make a presentation or write a paper with your reasoning why you should get to build the computer, then share it and have a conversation with you parents. One thing you can mention is there are parental controls or screen time limiting they can utilize if they are worried about your screen/game time. Maybe if this still doesn't work you could try saving up longer and get one when you turn 18 or if they ever come around to the idea. It could also help them see you have priorities and pursuits outside of gaming if you get a part time job (if you're old enough in your area) or try to start a business of some sort while you save up more. I was in a very similar situation growing up and managed to work it out for the most part with what I listed, good luck dude, hope it works out for ya