Kingston KSM24RD4/32MEI/KG01027490-001 Server Premier – DDR4-32 GB – DIMM 288-pin – 2400 MHz / PC4-19200 – CL17-1.2 V – Registered – ECC for CISCO UCS C-Series C220 M4 UCS-MR-1X322RV-A

What about Registered Memory?
Registered (often referred to as “buffered”) memory uses a technology that is often paired with, but not directly related to, ECC RAM.
Registered memory has a “register” that resides between the RAM and the system’s memory controller which lessens the load that is placed on the memory controller itself. This allows for more memory modules to be used at one time than would otherwise be possible.
While ECC RAM is not always Registered (since you may need the error correction of ECC without the large quantities made possible by Registered memory), almost all Registered memory will be ECC. This is simply due to the fact that systems that use large amounts of memory are almost always going to prioritize stability as well.
Capacity: 32GB
Type: 288-Pin DDR4 SDRAM
Speed: DDR4 2400 (PC4 19200)
Voltage: 1.2V
Dimm Type: RDIMM
Rank: 2Rx4
Cisco Part #: UCS-MR-1X322RV-A
Compatible with: Cisco UCS C-Series C220 M4