CrystalDiskMark may be a tool for measuring drive performance, but in a pinch it can also be used to hint if a flash drive (or memory card) is a fake.
When using CrystalDiskMark (in all tests mode) on drives which report a false capacity (the drive claims to have more storage than it actually does) the volume usage will increase, but the write test file may hold steady in size for quite some time while refreshing your view in explorer. This happens because some of the data is getting written back over sectors that were already used for the write test file so while the volume usage goes up the file size remains the same. On a legitimate drive the write test file should increase regularily in size along with the volume usage. This is not a definitive test, but if don't have access to proper testing tools this may at least raise a red flag that something isn't right about your device.
License:Ritchey Permissive License v6
Ritchey Permissive License v6:
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