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The Power 9 systems support two NVDIMMs per CPC/CEC in regular, but designated, memory slots. 

The size of a BPM is smaller than a standard 2,5 inch disk drive module and fits into one of the free CPC/CEC disk drive bays. In dependence of the config a maximum of two BPM modules will be installed per CPC. Figure 2-29 shows an example of such a BPM. 

<img src='content_image/1006224.jpg'>

As the logic resides on the NVDIMM and the BPMs are connected directly to them the movement of the DRAM to Flash works independently of the power state of the CPC/CEC itself and this is even true when the CPC/CEC is already turned off by power loss. 

The capability of the NVDIMMs is combined with the data protection concept of mirroring the write cache NVS to the alternative node. Chapter 3.2, “CPC failover and failback” on page 72 explains this in more detail. 

## 2.6.6 Power cord options 

The power cord must be ordered for specific input voltage to meet certain requirements. The power cord connector requirements vary widely throughout the world. The power cord might not include the suitable connector for the country in which the system is installed. In this case, the connector must be replaced by an electrician after the system is delivered. For more information, see the IBM System Storage DS8900F Introduction and Planning Guide , GC27-9560. 

## 2.6.7 Enclosure power supplies 

The CPCs, I/O enclosures, management enclosure and HPFE Gen2 feature dual redundant PSUs for each enclosure. The PSUs are supplied power from the iPDUs. Each PSU in an enclosure is supplied from different power domains for redundancy. That implies that the power comes from different iPDUs, one on the left and one on right side of the rack. The 

