SanDisk's new 256GB microSD Express and 2TB microSD cards

Posted by Constellation16@reddit | hardware | View on Reddit | 43 comments

SanDisk's 256GB microSD Express card and their 2TB microSD cards are now up for sale. Both were announced earlier this year.

After the initial uneventful release of SD Express cards 3 years ago, eg by Adata, this is the first of a new batch of announced cards on market. By absolute chance this all coincides with the upcoming release of a certain gaming handheld. The MSRP of 66€ is still 3x that of standard UHS-I cards, but it's already a lot lower than the market price of 90€ for the Adata card or often outrageous prices for UHS-II cards. SD Express utilizes PCIe/NVMe and reaches ~1GB/s full-duplex in this initial configuration.

Their new 2TB microSD UHS-I cards cost a staggering MSRP of 280€/320€. Despite announcements by others, these are the first actually for sale, I think. What I find most interesting about them though is that they use yet another variant of SanDisk's semi-proprietary "QuickFlow" technology (trademark for DDR200/DDR225/etc) that overclocks the UHS-I bus to exceed the typical 104 MB/s. The new iteration reaches 250 MB/s, which puts it close to the 312 MB/s of UHS-II. Both are half-duplex.

From what I understand the initial release of it in 2018 supported 170 MB/s, in 2022 this got bumped to 200 MB/s, and now 250 MB/s by specifically only these 2TB cards. Support in generic card readers or devices is basically non-existent though, so it's only useful to quickly copy over data by utilizing their special card reader. The new higher speeds require yet again new readers. By now there are also such cards and readers by Samsung, Lexar, Kingston, etc. The SD Association still hasn't standardized this technology though. Absolute mess.

The whole SD market is in a bit of flux right with multiple ways to achieve higher speeds. First this proprietary technology, then some newer more affordable UHS-II cards, even though support for it is still only slowly expanding outside cameras despite marginal extra cost in readers, and then the new SD Express cards which will hopefully just become the new standard.

Lately there have also been some UHS-II microSD cards for gaming handhelds like ROG Ally & co, when it has traditionally only been full-size cards for cameras. This development is likely short-lived, as I expected they will all quickly move to microSD Express.