While Google has the performance side of Stadia covered with a custom hyperthreading CPU plus and AMD GPU capable of delivering 10.7 TF of processing power, testers of the demo version pointed out that input lag is quite noticeable, and the image quality may be affected in dynamic scenes. Hopefully Google is taking notes and the final version releasing this summer will be better optimized.
https://www.notebookcheck.net/Hands-on-Google-Stadia-testers-report-noticeable-lag-and-mild-image-artifacts.414778.0.html