CrystalDiskMark is a useful benchmark to measure theoretical performance levels of hard drives and SSD’s. We are using V3.0.3. to test HDDs.
Although it's not mentioned on the spec sheet for the drive or in the features list, it appears that the Exos X16 – like the previous Exos X14 – uses Advanced Write Caching technology which boosts the random write performance of the drive, as can be clearly seen in the CrystalDiskMark write result.