PXE boot

My Zen 7SP1 server crashed, and I had to recreate the server and reinstall
Zenworks.

For imaging machines, I've been using a bootcd. That still works with the
new install. But now I need to use PXE (the bootcd doesn't properly
recognize the hardware in a dell GX620). I'm not sure if this has ever
worked, either pre or post crash.

When I boot a machine to PXE, if finds a Zenworks boot, with the server's
IP. It receives an IP via DHCP. Then it shows:
Action: Localboot
Zenworks shutting down...
PXE-M0F: exiting broadcom pxe rom

I never receive the imaging menu. My DHCP server has option #66 pointing
to the zen server's IP. The DHCP server is on a separate server from the
zen server. The server policy/imaging is set to always show the imaging
menu.

Any ideas on what I'm missing?