I take it the original Dell installed memory works OK, does it work in any memory slot? Sometimes, if new hardware (memory) is installed the BIOS will not recognize it unless the CMOS memory is cleared.  Try that with one new memory module in one slot.  To clear CMOS, power off, disconnect AC power cord, hold power button in for about 15 seconds.  Open the case and locate the CR2032 battery on the motherboard.  Remove the battery for at least 10 minutes then reinstall, reconnect AC power cord and try. Dell's have a history with memory compatibility and non-Dell branded memory.  Some brands work, some will not, some will work in one PC and not another.  For this reason, we suggest Crucial as it is guaranteed to work in a Dell.  If not Crucial we suggest buying it where they have a liberal return policy in case it doesn't work. Here is the Crucial listing for the 8930 [URL]
I have a Dell XPS 8930 with 8GB (1x8GB) stock RAM, 2400MHz, and an i3-8100 3.6GHz Intel processor. It currently runs fine. I recently bought a 64GB RAM upgrade kit (4x16GB): Micron PC4-2133P DDR4 MTA36ASF2G72PZ-2G1A2IG. Inserting any of the 16GB cards into any of the RAM slots, in any configuration, with or without the old 8GB stick present, results in a failed POST. The power light blinks amber four times, indicating a RAM read/write issue.   Things I have tried: Confirming the computer is plugged into the wall (instead of a power strip) Unplugging the computer and holding the power button for 10+ seconds (to discharge the capacitors) before installing RAM Testing the RAM slots on the motherboard (which work fine with the 8GB card) Many assorted RAM configurations, including the verified configurations outlined in the manual (2x16GB in XIMM1 and XIMM3, etc.) and including trying one stick at a time (to see if there's a bad stick throwing everything off). All have the exact same failure.   I am aware that the upgrade, at 2133MHz, is slower than the original RAM, but XPS 8930 should be fully capable of running at 2133MHz. I am aware that the i3-8100 has a RAM cap, but since the cap is 64GB, I should be fine. I have no way of testing the cards themselves, since I have no other computers that use DDR4 memory. But I highly doubt that all four are bad.   What's going on? Thanks in advance.
XPS 8930, 64GB RAM Upgrade Failure