Como minerar bitcoin com GPU?

Could you elaborate on the process of mining Bitcoin using a Graphics Processing Unit (GPU)? As a cryptocurrency enthusiast, I'm curious about the technical aspects involved. Specifically, what hardware requirements are necessary for GPU mining? What software should be used to facilitate the mining process? Are there any specific considerations for optimizing the mining performance of a GPU? Additionally, what are the potential risks and challenges associated with GPU mining? Lastly, how profitable is GPU mining Bitcoin compared to other mining methods in the current market?