ProLiant Servers (ML,DL,SL)

Re: Power Supply mismatch. Both are 460 watt. Bios bug?

New Member

Power Supply mismatch. Both are 460 watt. Bios bug?

I've bought an extra redundant power supply to my HP ProLiant DL385 G7.


When I plug it in, the server cannot start with the error "Power Supply mismatch".


But both power supply are 460 watt. Both have the same output specifications, and look the same. They report the same in iLO (but mismatch).


One night when I had a small service window I removed both and then I saw that the part numbers differs.


The original power supply that came with the server has spare part no 511777-001, and the one I bought (which is compatible with my server) has spare part no 599381-001. Further investigation tells me that the original is a Gold power supply with 92% efficiency, and the one I bought is a platinum high efficiency power supply with 94% efficiency. They both have the same output to the server but the platinum requires 2% less energy from the power company (which obviously does not affect the server from its power perspective).


The FAQ at tells me that I cannot put different wattage power supplies in the server at the same time. But they are the same wattage.


I suppose that the bios startup sequence compares the power supplies part numbers (which differs) and reports the mismatch error? Shouldn't the bios use the output wattage into account when determine if the power supplies match or mismatch?


Best regards,




Valued Contributor

Re: Power Supply mismatch. Both are 460 watt. Bios bug?

Hello Tom,


Mixing of power supplies is not a supported configuration even if have the same Watts.  Please take a look at this document.


Page #2:


It states:



HP Power Supplies

NOTE: Mixing of power supplies in the same server is not supported. All power supplies

must be of the same output and efficiency rating. If non-matched power supplies are

inserted you will get errors and operation will fail.


So its neccesary to have both power supplies with the same spare number (ej, both with 511777-001)




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