I purchased a refurbished PowerEdge R720 that had 64GB installed (8x8GB).

 

I have since purchase an additional 4x 8GB Memory Modules (ECC Registered DDR3) and am trying to get them installed so that I have a total of 96BG split evenly between the two CPUs.

 

Looking at the chart I found on the Dell Support website, it seems these are the slots that should be populate:

So I have made sure I have a DIMM installed in each of those slots. But unfortunately, only 80GB is being detected. two of the DIMMs are showing in iDRAC but are not counting (you can see they show 0GB) and for some reason some are showing Info not Available instead of the "DDR-3" indication.

What am I missing here?

 

Thanks!