In a previous post I explained how I managed to connect microSD Express cards as PCIe NVMe devices to a computer’s M.2 slot. This eliminates possible overhead and bias of USB adapters. Additionally, it allows extracting additional information via the NVMe interface. So let’s do some benchmarks ⏱️. I tested the following cards: 1TB Lexar® PLAY PRO (LX1TB71) 256GB ADATA Premier Extreme (SD71) 256GB Sandisk (ST25671_WDC/SDSQXFN) They all support PCIe Gen3x1 which supports a maximum theoretical transfer speed of 985MB/s per direction. ...
A microSD Express card in an M.2 slot
The upcoming Nintendo Switch 2 game console features microSD Express cards, which I hadn’t heard about before. Since I got nothing else to do while waiting for the console to release, I dug deeper into what these actually are. These microSD Express cards have additional pins for … 🥁 … PCI Express. This allows transferring data much faster compared to their SDIO interface. So I went looking online for adapters, which can connect these cards to a computers PCIe port. To my surprise, these don’t exist. Heck, even for USB, there’s only a single adapter that you can buy: SanDisk PRO-READER SD Express Dual Card. There are a couple more for full-sized SD cards, but SD<->microSD adapters don’t seem to exist, which makes them useless to me. ...