My laptop slows down significantly while plugged in

I have an Alienware 15 R2 (i7 6700HQ, 8GB RAM, GTX 970M) which slows down/hangs when I plug it in for charging. It used to work fine until a few months ago but it's unusable on power now. It also tends to overheat while charging. I can't even watch YouTube or use Chrome when it's charging. It's just incredibly slow. It works perfectly fine when it's running on battery. What could be the reason for this - and is there any fix for it?

Submitted July 29, 2017 at 11:36PM by arhanv http://ift.tt/2v6a6ao