My laptop has a speed of 2.50Ghz but as soon as i plug the charger in CPU drop drastically

[Timekeepar]

My laptop has a speed of 2.50Ghz but as soon as i plug the charger in (even when there's no power),it drops to 0.50ghz and below making the laptop very slow...When I remove the battery and restart it without plugging it,it goes back to its normal speed.I feel the charging port is damaged but I dont know why and how it affects the CPU speed and the system still charges well

this procedure has been done .

And all driver has been updated , even did a fresh install from recovery

Let's start off by ensuring the Windows is updated: 

1) In the search box, type and open Windows Updates. 

2) Check for updates. 

3) If the updates are available, click on install and restart the computer.

Next thing, I would suggest here is to update the Bios, Chipset and Graphics card drivers on your PC from our HP support website,using this link.

Also, download and install HP support assistant on your PC. It should automatically download and install the latest updates and drivers for your PC.

Refer this link to know how to use HP support assistant.

Here is a link to  HP Notebook PCs - Testing and Using the AC Power Adapter that will rule that possibility out.

Next  I would try restoring the default power scheme.

• Right click on the Windows button (lower left corner)

• Choose command prompt admin

• Type powercfg -restoredefaultschemes and press enter.

HP Notebook PCs - Managing Power Options (Windows 10)

Alternatively, I would suggest you can go through this link: HP PCs - Increasing System Performance and Maintaining Your Computer (Windows 10) that may also help.

Please let me know if this resolves the issue, or if you require further assistance!

Eagerly waiting for your response!

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give us some reinforcement by clicking the solution and kudos buttons, 

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