Question: what pc do you need to stream on twitch?
Answer: Twitch recommends that your PC has at least an Intel Core i5-4670 or the AMD equivalent, and 8GB of RAM. Your graphics card isn't as important a consideration for streaming, but Twitch says it should be at least DirectX 10 compatible. Though if you want to play a modern game, DirectX 11 or 12 is required.