For every hard drive, we ran HD Tune Guru, a benchmarking program that tests transfer rates, access time, burst speed, and CPU usage across the entire disk. We also timed a series of file transfers–a 7.07 GB folder of photos, a 19.7 GB audio collection, and also a 45.5 GB rip of a Blu-ray movie–from begin to finish, running each move three times and determining the average to rule out performance hiccups. We researched each drive’s bundled applications to learn how useful and user-friendly it’s.
For solid-state drives we used CrystalDiskMark and ATTO Disk Benchmark to test each drive’s sequential and random speeds, and we timed the exact same set of document transfers we utilize for hard drives. We ran all these tests on the Asus ROG G752VT-DH72, our very best gaming laptop. Its PCIe solid-state drive was more than fast enough to prevent bottlenecking all the drives we tested.
It is also smaller and lighter than the majority of the other hard drives we tested, was consistently faster than the competition in our multifile music and photo transfer tests, and it is one of the least costly drives per terabyte we analyzed, too. The Slim includes useful backup applications and 200 GB of free OneDrive storage for two years.
The Slim has been our top choice since April 2014, except for a three-month period when it had been superseded with its successor, the Seagate Backup Plus Ultra Slim. The Ultra Slim’s reported failure rate has skyrocketed since we began recommending it, so we’ve shifted our pick back to the Slim.
Back in January 2017 , we recorded 587 failure reports out of 8,948 user reviews for its Slim, giving the Slim a 6.5 percent reported failure rate–that’s especially great for a drive that has been in existence for three decades. (You can read more about how exactly we calculate failure rates in our full manual.) The 2 TB model we recommend has a much lower failure rate at 5.9 percent. Throughout our years of testing, we have found that anything below 10 percent isn’t cause for concern. That is far from a perfect measure, but it’s the best we have for today.