Hardware Maintenance Manual This manual contains service and reference information for ThinkCentre® computers listed on the cover. It is intended only for trained servicers who are familiar with Lenovo® computer products. Before servicing a Lenovo product, be sure to read the Safety Information. See Chapter 2, “Safety information,” on page 5. The Symptom-to-FRU Index and Additional Service Information chapters are not specific to any machine type and are applicable to all ThinkCentre computers. This manual includes a complete FRU part number listing for each machine type and model listed on the cover. This manual does not include procedures for replacing FRUs. For FRU replacement procedures, refer to the Hardware Replacement Guide for the appropriate machine type.