The Lenovo Legion T5 Gen 8 with AMD Ryzen 7 7700 and NVIDIA GeForce RTX 4070 Super offers several memory expansion options:

- SSD interfaces: It supports PCIe SSDs, and multiple M.2 slots are available to add additional SSDs. More specific details show that it can support up to 4TB of PCIe SSD storage capacity.
- SATA interfaces: SATA interfaces are also available to add traditional SATA SSDs or HDDs. However, the exact number of SATA ports are not explicitly stated in the sources, but it is common for such systems to offer multiple SATA ports.

To summarise, the system offers multiple M.2 slots for PCIe SSDs and probably multiple SATA ports for further storage expansion.