The HPE 900W Gold Redundant AC Power Input Module with Power Backplane can be configured to support power redundancy in ProLiant servers that offer only a single power supply bay, providing additional protection against power loss. With an 80 Plus Gold power efficiency rating up to 92%, this power option helps to reduce operating expenses while protecting against trapped power capacity in the data center. The HPE 550W FIO Power Supply is a non-redundant, Silver-certified 80 Plus power option (up to 89% efficiency) offering an optimized set of features at an entry-level price. Compatible across a wide range of HP ProLiant Gen9 Essential Servers providing a common power supply spares strategy that helps to reduce data center costs.