When trying to rollback a 14G BIOS to a previous version, it fails with the following error message:
UEFI0305: Unable to update BIOS firmware in the previous boot (Error Code = 0000000000000200)
Retry the operation. If the issue persists, contact your service provider.
With 14G servers, once BIOS version 1.4.5 or newer is installed, BIOS backflash is blocked for certain memory configurations (18nm technology RDIMMS), to prevent a system halt caused by a microcode issue in BIOS versions 1.1.7 or older
. BIOS version 1.2.11 or newer is required to support the new 18nm technology RDIMMs. PowerEdge C4140 servers are unaffected by this issue since all the released BIOS versions contain the corrected microcode.
NOTE: Even though the PowerEdge C4140 BIOS does contain the microcode that fully supports the 18nm technology RDIMMs, BIOS versions 1.2.4 through 1.2.7 incorrectly set the associated BIOS flag that prevents the backflash or update to a BIOS that does not have that BIOS flag set. PowerEdge C4140 BIOS version 1.6.11 removed that BIOS flag since it was technically not needed. If all three conditions listed below
are met, customers attempting to update from BIOS version 1.2.4/1.2.6/1.2.7 to version 1.6.11 or higher will also fail, with this same error message. The solution of how to update to 1.6.11 or newer in this case is the same as shown below
BIOS version 1.4.5 or newer will block BIOS backflash if all three of the following conditions are met:
- At least one 16GB RDIMM is installed that uses the new 18nm technology (see vendor part number examples below)
- Memory is populated in a 2 DIMMs Per Channel (2DPC) configuration (any black connector populated, more than 6 DIMMs per CPU)
- System memory speed is 2666 MT/s
Note: Starting with BIOS version 1.4.5, BIOS backflash requires the Dell Update Package (DUP) to be installed from the OS or from iDRAC. The UEFI BIOS update tool will no longer allow BIOS backflashing.
If BIOS backflash is required, and 18nm 16DIMMs are installed, one of the following three actions are needed:
- Reduce system memory speed to 2400 MT/s or 2133 MT/s, or
- Remove DIMMs to get the system into a 1DPC configuration, or
- Remove all DIMMs using 18nm technology
Micron 18nm 16GB DIMMs have been shipping into Dell factories since January. Samsung 18nm 16GB DIMMs started shipping to Dell factories in March.
The 18nm 16GB DIMMS can be identifed by looking at the PartNumber field in the iDRAC GUI - System -> Inventory -> Hardware Inventory and expand out the DIMM information:
This example shows a Micron 16GB DIMM. PartNumber 18ASF2G72PDZ-2G6D
1 is the part number for a 20nm DIMM. The 18nm Micron DIMM is PartNumber: 18ASF2G72PDZ-2G6E
For a Samsung 16GB 20nm DIMM, the PartNumber displayed would be M393A2K43B
B1-CTD. The 18nm Samsung DIMM is PartNumber: M393A2K43C