In the SanDisk line of memory cards Ultra is the budget choice. It is intended for compact to mid-level point-and-shoot digital cameras. The SanDisk Ultra 40MB/s UHS-I is the latest version of the card. The 40MB/s is the read speed, while write speed is lower but “twice as fast as ordinary SD cards.” According to SanDisk, ordinary means 5MB/s write speed, so this card must provide at least 10MB/s write speed, which is also the same minimum level of write performance other Class 10 cards must maintain. Ultra SD cards are available in 8, 16, 32, 64 and 128GB capacities. The 64GB SDXC version is reviewed here.
The Ultra 40MB/s 64GB SDXC card was benchmarked in various SD card readers. It exceeded its advertised read speed, reaching 47.9MB/s sequential read. Its sequential write speed measured between 14.9 and 16.1 MB/s in various readers. This is above the 10MB/s write SanDisk implies, but far from the speed offered by “high performance” SD cards.
Card: SanDisk Ultra 40MB/s 64GB
Benchmark: CrystalDiskMark 3.0.3 x64
Program settings: 1000 MB, 5 passes, random test data
Operating system: Windows 10 Pro
Motherboard: Gigabyte GA-Z77X-UD3H
Processor: Intel Core i7-3770K @ 4.40GHz
RAM: 32GB DDR3 1600