Sorry for the late reply!
First of all, boot into BIOS and figure out what version you have now, just to make sure.
It's usually printed somewhere on the first screen you see.
If your BIOS version is less than v1005, you can try to update it. (Mine was v0805)
Now go here and download the latest BIOS update: https://www.asus.com/Motherboards/ROG-STRIX-Z390-E-GAMING/HelpDesk_BIOS/
Latest version is v1005 (as of writing this), and in the notes i see "Improved DRAM compatibility", which might be able to solve your problem as it did for me!
After downloading, unzip the file and put it on a USB drive.
Boot into BIOS, find the tab named "Tools" and click "EZ Flash" (or something like that, you can probably Google it if you can't find it).
Follow the instructions and pick the file from the USB when asked. Important:
Make sure that your system will NOT lose power during the update process, as this can break your motherboard!
Double check that the power cable is plugged properly in before updating, and don't update during thunderstorms
I really hope this works for you as it did for me. Seeing the DRAM note on the driver for your board makes me think it might do!
Let me know if it works