Hardware Asylum checked out the SilverStone ECM22 M.2 to PCIe Expansion Card
A quote from the article:
Let's face it SSDs have become the defacto storage platform for almost every type of computer. Gaming PCs have them to load games and maps quicker, workstations have them for fast load times and memory caching and servers are using them cause, well, speed is a good thing. The challenge comes when you realize to get the fastest SSDs you need to use NVMe M.2 drives and don't have the appropriate slot on your motherboard.SilverStone ECM22 M.2 to PCIe Expansion Card Review @ Hardware Asylum
In this review I'll be looking at two companion products from SilverStone. The ECM22 M.2 to PCIe Expansion card and the TP01-M2 SSD thermal pad. You buy these separately and work quite well together.