Compaq Pro 6305 Maintenance and Service Guide Pro 6305 Microtower Business PC - Page 159

Computer will not respond to keyboard or mouse. Cause Computer is in Sleep state. System has locked up. Solution To resume from Sleep state, press the power button. CAUTION: When attempting to resume from Sleep state, do not hold down the power button for more than four seconds. Otherwise, the computer will shut down and you will lose any unsaved data. Restart computer. Computer date and time display is incorrect. Cause RTC (real-time clock) battery may need to be replaced. NOTE: Connecting the computer to a live AC outlet prolongs the life of the RTC battery. Solution Reset the date and time under Control Panel (Computer Setup can also be used to update the RTC date and time). If the problem persists, replace the RTC battery. See the Removal and Replacement section for instructions on installing a new battery, or contact an authorized dealer or reseller for RTC battery replacement. To access Control Panel in Windows 7, select Start, and then select Control Panel. To access Control Panel in Windows 8, from the Start screen, type c, and then select Control Panel from the list of applications. Cursor will not move using the arrow keys on the keypad. Cause Solution The Num Lock key is turned on. Press the Num Lock key. The Num Lock light must be off if you want to use the arrow keys on the keypad. You can also disable or enable the Num Lock key in Computer Setup at Advanced > Device Options. There is no sound or sound volume is too low. Cause System volume may be set low or muted. Solution 1. Check the Computer Setup settings to make sure the internal system speaker is not muted (this setting does not affect the external speakers). 2. Make sure the external speakers are properly connected and powered on and that the speakers' volume control is set correctly. 3. Use the system volume control available in the operating system to make sure the speakers are not muted or to increase the volume. Solving General Problems 149