We have a R430 that reports error on the iDRAC
When powered on it hangs on "Initializing iDRAC" and don't get any IP.
The fans are running at full speed and the console it reports;

SWC07000: iDRAC is not ready. The configuration values cannot be accessed.
UEFI0315: Unable to process an iDRAC request to configure Secure Boot keys....
UEFI0029: Unable to initialize iDRAC because of some critical issues

LifeCycle Manager is disabled. Also if I try to make changes in BIOS, it errors out when trying to save.
I have tested to swap the iDRAC card with one from a working R530 server. Same issue.
I have also upgraded the BIOS to the latest version.
Also tested stripping the whole server for mem/controller/disks etc...
And reset BIOS / remove BIOS battery.

Any ideas?
MB replacement next?