How we test
Our benchmarks were run on our test rig which uses Windows 10 Pro 64-bit. On the inside, it has a 3.5GHz Intel Core i7 4770k processor, 16GB (1600MHz) RAM, an Intel DZ87KLT75K Haswell Z87 motherboard and an AMD Radeon R9 390 graphics card.
When conducting our tests, we plugged in our portable storage drives into one of our motherboard’s rear USB 3.0 ports. Like the vast majority of PCs and laptops, it does not support USB 3.1 Gen 2, however, Gen 1 ports should (theoretically) be able to handle up to 625MB/s and none of the drives on test is rated beyond 550MB/s.
We used CrystalDiskMark 64-bit to test each drive’s speed. We selected 1GB test files and three test passes in order to determine both sequential and 4KB performance
Where a drive could be connected to a phone or tablet, we did so an installed any relevant Android or iOS apps.
The price per gigabyte for each of the drives in this group test was calculated on real-world storage.