Very useful Now that USB 2.0 has been banished from all self-respecting storage, we find USB 3 as the standard for connection, letting these portable drives perform as quickly as the little disks inside will allow.
This means that when transferring your music or video collection to or from your PC, you can expect around 100MB/s read speed ( and typically the same for writing, since unlike flash storage technology the read and write speeds tend to be more symmetrical) . Compare this with the older drives using USB 2.0, which would limit speeds to around 35MB/s, or only one-third the speed. So in real terms, your 100GB of media files would take close to an hour to transfer with USB 2.0, or under 20 minutes using USB 3.0.
If you’re likely to be storing or backing up many small files, be aware that overall performance will plummet since hard disks tend to choke on smaller files. So while large files may zip across at 100MB/s, the smallest will likely travel at less than 1MB/s, or one hundredth that speed.
USB 3 is confusing, as USB 3.0 was retrospectively renamed to USB 3.1 Gen 1. There’s also a new version, USB 3.1 Gen 2. This doubles the potential throughput from Gen 1’s 5Gb/s to 10Gb/s. In megabytes per second, these equate to 625 and 1250 respectively. Pretty fast, then. In reality, the fastest SSDs top out at around 550MB/s and this speed is highly dependent on the device you’re connecting it to.
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