You can tell SanDisk's performance numbers do not add up and that they are likely misrepresenting the true performance of their device. (Those red asterisks nex

You can tell SanDisk's performance numbers do not add up and that they are likely misrepresenting the true performance of their device. (Those red asterisks next to the numbers correspond to a footnote that is conveniently missing from the page...) A "read latency of 150usec" translates to maximum possible read IOPS rate of 1/150e-6 = 6.67K (with one outstanding I/O). But they quote a "random read IOPS of 140K". That would only be possible if their DDR3-based DIMM could process 21 concurrent read I/O operations. But to the best of my knowledge, DDR3 is limited to 8 banks/DIMM, so there could not possibly be more than 8 concurrent read I/O at any one time. Far from 21. So SanDisk is likely quoting a worst case read latency and/or a best case read IOPS. Customers are left to themselves to figure out which of these numbers is most likely to represent the average performance... PS: here is a paper with some more details but that still fails to explain this discrepancy: http://www.snia.org/sites/default/files/SanDisk%20ULLtraDIMM_0.pdf http://www.snia.org/sites/default/files/SanDisk%20ULLtraDIMM...