The 7i will most likely be powered by Comet Lake-H Core i7 CPUs and will feature the latest RTX 2000 Super GPUs, while the 5i will pack Comet Lake-H Core i5 CPUs and up to an RTX 2060 GPU. Both variants will get G-Sync displays plus a n exclusive feature developed in collaboration with Nvidia, which allows for a more efficient battery management.
https://www.notebookcheck.net/Lenovo-s-Legion-5i-and-7i-gaming-laptops-include-the-exclusive-Nvidia-Advanced-Optimus-feature-for-extended-battery-life.459738.0.html