gpu is a good one thanks for the advice.
but will it conform to the specs of my PC.i don't want to change anything else except for the gpu.
i believe this is what you advised http://homeshopping.pk/products/ASUS-R7-250-Graphics-Card-Price-in-Pakistan.html
Yup, that's the one. It's a pretty small card so it should physically fit in your case without any issues. You won't need to buy a new psu either.