Retro-Bit Prism HDMI Adapter for GameCube - AV to HDMI Converter/Upscaler

Retro-Bit Prism HDMI Adapter for GameCube - AV to HDMI Converter/Upscaler

It does exactly what the title says, it upscales Gamecube from AV to HDMI. 

I have used and tested this product and it does a great job. Please look up reviews for this product to see if it is the right fit for you.