The SK Hynix Gold S31 is a solid-state drive in the 2.5" form factor, launched on August 15th, 2019. It is available in capacities ranging from 250 GB to 1 TB. This page reports specifications for the 250 GB variant. With the rest of the system, the SK Hynix Gold S31 interfaces using a SATA 6 Gbps connection. The SSD controller is the Quartz SH87830CC from SK Hynix, a DRAM cache chip is available. SK Hynix has installed 72-layer TLC NAND flash on the Gold S31, the flash chips are made by SK Hynix. To improve write speeds, a pseudo-SLC cache is used, so bursts of incoming writes are absorbed more quickly. The cache is sized at 4 GB, once it is full, writes complete at 146 MB/s. The Gold S31 is rated for sequential read speeds of up to 560 MB/s and 500 MB/s write; random IO reaches 54K IOPS for read and 87K for writes.
At its launch, the SSD was priced at 38 USD. The warranty length is set to five years, which is an excellent warranty period. SK Hynix guarantees an endurance rating of 200 TBW, a typical value for consumer SSDs.