This message was posted on behalf of Intel Corporation
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OEM versions of Intel® SSD use a different firmware revision than the retail versions. Intel® SSD Toolbox and other Intel tools used for SSD firmware updates work with retail drives only.
It seems the Dell* version of Intel® SSD 750 Series has a unique firmware. However, we recommend to contact the OEM to confirm this.
Let us know if there's anything else we can do for you.