Upgrade help?

So at the moment my processor is an amd a10-5800k with integrated hd graphics(AMD Radeon HD 7660D) and Christmas is coming up. Therefore my question is what graphics card should i get, i can't get anything to expensive do to the fact I'm in high school and I don't have a job.

Also I have a corsair 500w 80+ power supply.

 

Thank you for your help!

 

well I hear that an radeon HD 7770 or a 7850 are both pretty decent and not too expensive. whats your price range your looking for? 

come to think of it ive also heard a few people mention adding a radeon HD 6670 in crossfire with the APU to give it an extra bump. this is  apretty cheap option but i dont know particularly how much of a boost you gain from it.