UEFI Boot Looping While Initializing Devices

[real]

Hello,

I am running a test server, attempting to boot both BIOS and EFI clients. My test client is a Dell Optiplex 9010. I can serve and boot to undionly.kpxe exactly as expected, but, when I boot to any of the efi binaries that I'm aware of (ipxe.efi, snponly.efi, realtek.efi, snp.efi), it fails.

With all of the above mentioned except realtek.efi, the boot hangs at "iPXE initializing devices" with iPXE attempting and failing to start NII and SNP drivers in an infinite loop, as shown in the included picture. When searching for answers for this, I find a somewhat related post here: http://forum.ipxe.org/showthread.php?tid=7877.

When I boot with the realtek binary, it immediately loads and displays the Ctrl-B prompt reports "No network devices" and sends me back to the boot menu.

Thanks for your time,
real