HP ZBook 17 Maintenance and Service Guide - Page 160

Items Procedures See https://support.hp.com/us-en/document/c01657439. Noise (sound) Items Procedures Symptoms Computer emits abnormal noise Possible causes Aside from basic components (power adapter/supply, fan, speaker, hard drive, optical drive, display panel, external devices), it is also common for electronic components to produce noise. Troubleshooting steps 1. Inspect external power source and change to verified working one. 2. Determine whether the noise comes from AC power adapter. Test with a verified working AC adapter. Disconnect external devices and all cables connected to the computer to isolate issue to computer only. Noisy fan Determine whether the noise comes from the fan. Disconnect the fan briefly to isolate whether noise originates from fan. If noise is absent with fan disconnected, refer to Fan runs constantly on page 147. Noisy hard drive Determine whether the noise comes from the hard drive. See Noisy hard drive on page 144. Noisy optical drive 1. Determine whether the noise comes from an optical drive. 2. Remove CD/DVD from the optical drive. Noisy speaker 1. Determine whether the noise comes from speaker. 2. Test with a verified working external headset/speaker. Noisy display Determine whether the noise comes from display panel (humming noise). Change display frequency settings. See Display on page 126. The section below is intended for authorized service providers/technicians. 1. After disassembling the chassis, inspect components of the interior for excessive wear or damage. 2. If noise issues persist, proceed with process of elimination for battery, AC adapter, or boards. 146 Chapter 7 Troubleshooting guide