dumb question? prom chip for '03 grand prix gt

Start here;

Read a few links and see if the price for what you get is ok with you. A suggestion for the future. Do a little research on your own before asking blanket questions like this. You will be better informed so you will have a better idea of what you are really looking for.

Don't forget, Google is your friend! LOL

there is no single chip to replace. you would actually install a reprogrammed PCM, which most require other mods to the car such as exhaust and air intake