The Silicon Power UD90 is a solid-state drive in the M.2 2280 form factor, launched on May 20th, 2022. It is available in capacities ranging from 250 GB to 2 TB. This page reports specifications for the 1 TB variant. With the rest of the system, the Silicon Power UD90 interfaces using a PCI-Express 4.0 x4 connection. The SSD controller is the PS5021-E21T from Phison, a DRAM cache is not available. Silicon Power has installed 176-layer TLC NAND flash on the UD90, the flash chips are made by Micron. 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 absorbed more quickly. The cache is sized at 69 GB, once it is full, writes complete at 1800 MB/s. Copying data out of the SLC cache (folding) completes at 275 MB/s. Thanks to support for the fast PCI-Express 4.0 interface, performance is excellent. The UD90 is rated for sequential read speeds of up to 4,800 MB/s and 4,200 MB/s write; random IO reaches 570K IOPS for read and 600K for writes.
At its launch, the SSD was priced at 110 USD. The warranty length is set to five years, which is an excellent warranty period. Silicon Power guarantees an endurance rating of 600 TBW, a typical value for consumer SSDs.