The following table provides the different storage options available on XPS 13 7390.
M.2 2230 solid-state drive
PCIe NVMe Gen3 x2 NVMe, up to 32 Gbps
Up to 256 GB
M.2 2280 solid-state drive
PCIe Gen3 x4 NVMe, up to 32 Gbps
Up to 2 TB