RE: Dell M.2 / NVME Specifications And Upgrade Requirements For Latitude, XPS, Precision Mobile and Optiplex
Yes, you can install a 2.5 inch drive when you have the 4 cell battery. You'll need to remove the 2280 drive in order to do so. Adding a 2242 to the WWAN slot would be optional at that point.
That user guide bit also does not look right to me. I'm able to configure a 2280 and a 6 cell battery with no errors in my sales tools. I'll see about getting the document corrected.
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