Chapter 5. Customer replaceable unit partsThe replaceable components that are available for the 42U Enterprise Primary Rack and 42U EnterpriseExpansion Rack are described in this chapter.For an updated parts listing, go to http://www.ibm.com/supportportal/.Replaceable components are of three types:• Tier 1 customer replaceable unit (CRU): Replacement of Tier 1 CRUs is your responsibility. If IBMinstalls a Tier 1 CRU at your request, you will be charged for the installation.• Tier 2 customer replaceable unit: You may install a Tier 2 CRU yourself or request IBM to install it, at noadditional charge, under the type of warranty service that is designated for your server.• Field replaceable unit (FRU): FRUs must be installed only by trained service technicians.For information about getting service and assistance, see “Getting help and information from the World WideWeb” on page 22. For information about the terms of the warranty , see the Warranty Information documentthat comes with the rack cabinet.1 2 34789125101112 613© Copyright Lenovo 2001, 2010 19