RE: Latitude 5480 memory upgrade problem
Having completely the same issue here (Latitude E5480) with Patriotn Viper 2x16GB memory - PV432G240C5SK
Maximum I can get is 20GB (4GB original in DIMM_B + 16GB new in DIMM_A)
Dell support (on chat) was not able to help.
Upgraded BIOS to the most recent version (1.5.2) - did not help.
Tried to reset RTC (hold power button for 25 sec according to user's manual) - did not help.
Tried to remove battery and disconnect BIOS battery on MB - did not help.
Don't know what else can be done. Probably it's some BIOS issue. We might need to push Dell support to escalate the issue to L3. Maybe they'll be able to fix the BIOS.