HP 64MB Battery Backed Write Cache (BBWC) Enabler 641/642
Hewlett-Packard Part# 291969-B21
The BBWC Enabler transportable 64-MB battery module increases the total memory of the controller to 128-MB for code transfer buffers and read and write cache. The transportability of the battery memory module protects the write cache data from unexpected power loss system board failure or controller board failure. Data retained in the write cache will be protected for up to 72 hours allowing time to restore power or transport the module to a functioning system board or array controller.
The modular design of the battery memory module is transportable between the Smart Array 641 and Smart Array 642 controllers. 64-MB BBWC (Battery-Backed Write Cache) Enabler allows the 641/642 controllers an option to add transportable BBWC for improved controller performance and increases the total controller memory to 128-MB.