Why you may not be getting the SSD you paid for
The SSD you’ve bought may not be exactly the SSD you think it is. That’s because of a common vendor practice of swapping out internal parts due to supply, pricing pressure, or other reasons.
Usually this practice has focused on the NAND flash storage modules on SSDs, and the vendor has met or exceeded the promised specification. If the change is, the company changed the SSD controller without changing the name—except the performance changed, for the worse. There was no way of knowing the difference from the outside.
