I have see on different servers, from multiple hardware vendors, showing false warnings/Alerts under the hardware status, like this.
When looking at the hardware in IMM/ILO/iDRAC/… it does no show any errors.
What I have found is that this might be inconsistense between Firmware/BIOS/…. on the hardware and the vendors CIM modules
But it may also just be a record in the IPMI log, from an old error, so just do a reset of this log, fixes the problem.
After the reset event log, wait until the log is empty, or just ~1 log event saying that the log was cleaned/emptied. You may need to reset event log, more then once, but wait 5 minutes between the execution of reset event log.