PE SC1425 Mac address not present

Guys, I have a PE SC1425 that's not showing any mac addresses on integrated nic1 & 2. (shows a not present). So obviously when it boots into windows no nic ports are picked up in device manager (windows). I fitted another system board and this still has the same problem. am I missing something or does it look like another faulty system board. Booted up into Dell livecd and this doesn't detect any network ports.