guys pls help some new Dell laptops at the imaging bench PXE boot, some don't. The failing ones end like this:

>>Start PXE over IPv4.
Station IP address is 10.20.40.117
Server IP address is 10.20.1.15
NBP filename is
NBP filesize is 0 Bytes
PXE-E53: No boot filename received.
>>Start PXE over IPv6.
PXE-E16: No valid offer received.
Boot Failed. EFI Network.
same VLAN, same DP. the only difference i can see is firmware settings, but i dont know which ones matter.
the working and failing machines are teh same model, just bought at different times, some came with different firmware defaults, which BIOS or UEFI settings usually matter for PXE with ConfigMgr? what am i doing wrong??



