HP EliteDesk 800 Maintenance and Service Guide - HP EliteDesk 800 G1 Tower, HP - Page 148

5. Disconnect the fan cable from the system board connector labeled CPUFAN (1), and then lift the heat sink from atop the processor (2). When reinstalling the fan sink, make sure that its bottom has been cleaned with an alcohol wipe and fresh thermal grease has been applied to the top of the processor. CAUTION: Fan sink retaining screws should be tightened in diagonally opposite pairs (as in an X) to evenly seat the fan sink on the processor to avoid damage that could require replacing the system board. Make sure to replace the fan duct. Failure to install the fan duct may cause the computer to overheat. Processor Description Intel Core i7 processor 4770, 3.4 GHz, 8-MB L3 cache, 86W Intel Core i5 processors 4670, 3.4 GHz, 6-MB L3 cache, 86W 4570, 3.2 GHz, 6-MB L3 cache, 86W Spare part number 727373-001 727381-001 727380-001 1. Prepare the computer for disassembly (Preparation for disassembly on page 94). 2. Remove the access panel (Access panel on page 95). 3. Remove the fan duct (Fan duct on page 124). 4. Remove the fan sink (Fan sink on page 135). 136 Chapter 6 Removal and replacement procedures: Small Form Factor (SFF)