Hi,
Just checking have you tried:
i) A bare metal windows/linux install and verified if it picks up DHCP ok?
ii) if so and DHCP is working on it are you using NIC teaming on the server? if you are maybe break the team at the switch end and work off
one nic during the install.
iii) if using a single nic and i) worked i'd check to see if there is a customizable ISO boot installation CD for your version from the HP site as it will
have the latest drivers etc suitable for thet esx version.
Many tx