updated 06:13 pm EST, Thu November 7, 2013
New cards move between 104MB and 312MB per second speeds
The SD Association that controls the guidelines for SD storage cards today announced a new high-performance option and symbol specifically designed to support a wide array of 4K or 2K (the latter also known as 1080p or "Full HD") television and video products. A new Ultra High Speed (UHS) Speed Class 3 (U3) symbol will indicate products capable of recording 4K or 2K video and will operate exclusively on SDXC UHS-I and UHS-II memory cards and devices and SDHC UHS-I and UHS-II memory cards and devices.
The UHS Speed Class 3 has defined 30MB per second constant minimum write speed to ensure high-quality video recordings for the new standard. Cards that meet the new spec will be able to record 4K or 2K video, live broadcasts, and other high bit-rate content on high-performance cameras such as Digital Single Lens Reflex (D-SLR), Digital Single Lens Mirrorless (D-SLM), camcorders and video cameras.
New devices offering the UHS Speed Class 3 will be backwards compatible, and will work with existing SD memory cards. UHS-I cards are capable of pushing up to 104MB per second, with UHS-II cards supporting speeds up to 312MB per second.