Powerlifting is a sport. You don't just do powerlifting. You have to lift some heavy ass weights first, gain some muscle and then enter a powerlifting competition. Powerlifting alone won't do anything for your boxing. Strength training via weight lifting will give you strength (there IS a difference between powerlifting and weight training) and may help your boxing training.

I lift weights but not because I'm a boxer.

"does it help with your boxing training or make it worse?"

Most of the boxers that I know of do some kind of weight training, so I'm guessing that it'll do you good. It gives you power which is a key to knocking an opponent out in boxing.

It depends on who you talk to. First off i should tell you that weight lifting strength is different from boxing strength. Powerlifting is in short bursts and thats not gonna help much in a boxing match.

I just weight lift with high reps in order to have a solid stong body in the ring. That way my body is strong enough to take punishment when it has too. And it helps when things get rough to be an overall stronger fighter.