We have 30 Gateway E4400's with 3C905C-TX Nic's in them, but I can't get
them to boot correctly.

In the bios I have it set to boot from MBA UNDI first, and then floppy,
cd, ide-hdd. Everything looks fine, it boots into the managed boot agent
which is configured for PXE, boot failure wait for timeout, next bbs
device. The machine boots, finds our zenworks server, sees that there is
no imaging work, and then it says:

Network boot aborted or terminated.
Zenworks Preboot Management
Warning: PXE could not be detected
Zenworks Preboot shutting down

and then it just hangs there with a blinking cursor.

Any ideas?