The Addlink S91 is a solid-state drive in the M.2 2230 form factor, launched in April 2023. It is only available in the 512 GB capacity listed on this page. With the rest of the system, the Addlink S91 interfaces using a PCI-Express 4.0 x4 connection. The SSD controller is the PS5021-E21T from Phison, a DRAM cache is not available. Addlink has installed 112-layer TLC NAND flash on the S91, the flash chips are made by Kioxia. Please note that this SSD is sold in multiple variants with different NAND flash or controller, which could affect performance, the "Notes" section at the end of this page has more info. To improve write speeds, a pseudo-SLC cache is used, so bursts of incoming writes are processed more quickly. Thanks to support for the fast PCI-Express 4.0 interface, performance is excellent. The S91 is rated for sequential read speeds of up to 3,600 MB/s and 2,300 MB/s write; random IOPS reach up to 400K for reads and 550K for writes.
At its launch, the SSD was priced at 53 USD. The warranty length is set to five years, which is an excellent warranty period. Addlink guarantees an endurance rating of 350 TBW, a typical value for consumer SSDs.