HP StorageWorks 500 G2 Modular Smart Array - Manual (Page 55)

Hardware options installation 55
3. Install the controller.
4. Verify that the component is seated properly by observing its LEDs when the
storage system is at full power.
Cache module upgrade option
The MSA500 G2 controller ships with a 256-MB battery-backed cache module.
A second 256-MB battery-backed cache module is available as an option.
Cache module installation requirements
Observe the following guidelines:
• Always power down the storage system when performing a cache upgrade.
• If a controller has more than one cache DIMM, be sure that both DIMMs
have the same memory capacity.
• Always upgrade the cache in both controllers in a storage system with
redundant controllers.
• In a storage system with a redundant controller, be sure that both controllers
have the same number of DIMMs and that all DIMMs have the same
memory capacity.