32GB Memory (4x4GB DIMMS) in BL460c G1 with 2x X5460 CPUs

[lachico]

I have 6 BL460c G1 blades, each with two Xeon X5460 3.16Ghz (120W) cpus.  For each blade, I have 32GB (8x4GB) of 2Rx4 PC2-5300F-555-11-E1 DDR2 memory (PN 398708-061).

When I populate the servers with 16GB (4x4GB) FDIMMS everything works fine. When I populate with 32GB (8x4GB) then I get a mixture of POST messages with error 207 - Memory sizes don't match, or the server fails to boot at all / turn on. 

When I populate the server with 24GB (6x4GB) I get the same behavior (post errors / machine wont turn on at all / blank screen). 

But looking through the docs, it seems like 32GB (8x4GB) is a valid configuration? Is it not valid? Is there something I need to configure in ROM do to make this work?

OA Firmware is 4.40, iLO2 is 2.27, System ROM: I15 05/02/2011, 2x Xeon X540 CPU

Thanks so much in advance for the help!

-Mike