According to your description, I suggest you refer to the following information:
1. The power adapter is used to supply power to the host and charge the battery, which can reduce the voltage of 220V AC to a voltage suitable for notebook computers. In the process of current conversion, there will be electromagnetic vibration sound generated by electromagnetic phenomena and a certain amount of heat, which is a normal phenomenon. You don't have to worry about it. 2. If the current sound of the power adapter suddenly becomes louder, and the power adapter can't be used for power supply alone, you should immediately unplug the power adapter, shut down the machine, and send it to the HP service center for testing together with the power adapter, so as to prevent the machine from being damaged by voltage instability caused by the power adapter failure. You can contact your local HP Gold Service Center for on-site hardware maintenance.
For the contact information of HP Gold Service Center, you can use the following official links to inquire:
/zh/support-drivers/e support/as CPPS . html
I hope the above reply can help you. If the above information can't solve your problem, you can log on to www.hp.com.cn/chat,, the online chat room of HP Network, and ask an online engineer to help you solve the problem further.
More product information is available in www.hp.com.cn/800..