HP ProBook 640 G5 Does Not Power On

Your HP ProBook 640 G5 does not respond when the power button is pressed. The screen remains black without power and the laptop shows no lights, fan activity, or other signs of power. This problem is commonly caused by issues with the power button, battery, or other internal components. Follow the steps below to troubleshoot.

If the power button or its internal cable is damaged, the laptop may not respond when the button is pressed. Over time, the button mechanism can wear out or the internal connector may become loose, preventing the signal from reaching the motherboard.

Solution

Press the power button several times to check if it feels stuck or unresponsive. If the button does not click normally or requires excessive force, the internal switch may be damaged.

You can also test whether the laptop powers on by briefly disconnecting and reconnecting the internal battery or AC power to see if the system responds.

If the power button assembly is faulty, it may need to be replaced.

Follow this repair guide to replace the power button:

HP ProBook 640 G5 Power Button Replacement

Laptop batteries degrade over time and may eventually lose the ability to hold or deliver a charge. A fully depleted or damaged battery can prevent the laptop from powering on.

Solution

Make sure you are using a charger that has been confirmed to work on another device.

Connect the charger to the laptop and allow it to charge for at least 15-30 minutes before attempting to power it on again.

If the laptop still does not power on while connected to power, the battery may need to be replaced.

Follow this guide for battery replacement:

HP ProBook 640 G5 Battery Replacement

Improperly seated or damaged RAM can prevent a laptop from completing its startup process. In some cases, the device may appear completely unresponsive if the memory is not functioning properly.

Solution

Listen for repeating beep patterns or watch for blinking lights on the Caps Lock or Num Lock keys, which can indicate a RAM failure.

Power off the laptop and disconnect the charger. Open the bottom panel and locate the RAM modules.

Remove the RAM sticks and reseat them firmly in their slots. If the problem continues, test the laptop with one RAM module at a time to identify a faulty stick.

Follow this guide to access the internal components:

HP ProBook 640 G5 RAM Replacement