Same here on a R610... but with just one failed DIMM (one 8GB stick
out of total 48GB).
Since our rig was fine before as well and just the BIOS update to 6.3.0
somehow 'broke' it - I'd too suspect the new BIOS to be a bit flaky.
(looking at the release notes they even claim to have changed sth with regards
to the memory reference code)
But on the other hand - it's quite uncommon that possible problems wouldn't
have been noticed by someone else before (since the BIOS 6.3.0 release date
seems to be 2012-08-15).
Is there any progress with regards to this issue on your side?
TIA!