Hi [NAME],   I assume H200A is a PERC card that was tried to isolate the issue, the PE R820 is compatible with Series 8 Family PERC Controllers, whereas the H200A falls under the 6 & 7 series PERC controllers.   Please try the installation procedure using one of the following RAID controllers H310, H710, H710P, and H810.
First-time poster here, after exhausting all my googling abilities I am stuck. I have an R820 that I received second hand and it appears that the backplane was never used by its first owner, as none of the power/signal/SAS cables were connected, and the bays were all filled with blanks. The server would boot and run fine off a USB flash drive, but when attempting to connect a RAID card and make use of the backplane I continuously get stuck on the Initializing Firmware Interfaces screen.    Looking in the idrac logs the following exception occurs around the time in which the server appears to hang.  [IMAGE] In an attempt to remedy the issue I tried first removing the raid card, which allowed the system to boot normally. Replacing the generic raid card with an H200A yielded the same results as the other card, and the H200A was pulled from a working system moments before in an attempt to isolate the issue.    Furthermore, this only happens when the raid card is connected and a logical disk is configured. Destroying the array and attempting to boot allows the system to post and boot fine. I'm at my wits end on this one, as I can't figure out why a healthy raid array would cause a system hangup like this. All firmware is current to my knowledge, the lifecycle controller does not report any updates available. I unfortunately don't have any extra hardware to test with beyond what I have already done.    I have tried fully resetting the system to factory defaults using the built-in method on the lifecycle controller, as well as continuously trying to change settings and power cycling the system to see if I could find any conflicts within the BIOS. Another weird artifact I found during the process was that when trying to boot in UEFI mode, the raid configuration utility will never be loaded. Upon requesting the array config utility during startup, I get a message stating that the utility will load after firmware initialization is complete, but after initializing I get dumped straight into the boot sequence.    Happy to post any further explanations/logs/photos upon request. Any help is greatly appreciated! 
R820 Stuck At Initializing Firmware Interface