Thanks, I just checked and there is only 1 EFI partition. [IMAGE] We use intel RST and RAID 1 over 2x 512GB NVME drives. There is also a 3rd hard disk installed, as seen in the screenshots. Here is how the duplicate boot entries look like: [IMAGE] [IMAGE] However dell just released a new bios update 2.1.0 for the precision 3660. I installed it on the machine where I took above screenshots, then did a bios reset to remove all duplicate entries. Now there are no more duplicates created, even after many reboots / pxe boots. So fingers crossed that this is solved - even without anything matching in the update release notes [URL]    
We see some strange behavior on the precision 3660 model. On each reboot, a duplicate boot device is created and added to the boot device list. After a certain amount of reboots, the boot device list is so long that we don't even see the pxe boot option anymore (even when scrolling all the way down). Resetting the BIOS removes the duplicates, but still each subsequent reboot adds another duplicate of the same boot device (a samsung NVME ssd). At one point I couldn't even launch the one-time boot menu, supposedly because there were so many boot device entries.  This happens on multiple devices of this model. I will do some more tests and take screenshots. In the meantime, has anyone experienced this behavior before?   
Many duplicate boot devices