Hi Tahmid,
Thank you for your supplementary explanation, but whether it is a hardware problem still needs to be solved.
Here's what to do now: Back up all your important data, then create a Surface-specific USB recovery drive to fully restore your Surface to factory Settings:
The link provides a complete video guide to downloading a suitable recovery image, creating a dedicated USB recovery drive, and using the correct process to reinstall your system for your Surface.
After all of this is done, please re-verify that your Surface still has the abnormal performance degradation when connected to the power adapter.
If the problem does not occur again, please continue to use and observe, but I believe the problem should be completely resolved.
But if the problem comes back, then obviously the problem originated in the hardware, because the system is completely redeployed, there should be no exceptions, and there is no interference from any third-party software. Turning your Surface over to the Surface support team for inspection is my final recommendation.
I can guide you through the right steps to get in touch with them:
Open the Surface App (usually built into your Surface device, or you can download it from the Microsoft Store if you don't have one) and follow the procedure below:
- Click "Help and Support" and then click "Get Help".
- Briefly describe your problem in the text box, such as "Surface performance deteriorates when plugged in", and then press Enter.
- Click "Contact Support" at the bottom.
- Select Surface and select the model, then click Confirm.
- You will see "Chat support" or "phone support" options, please contact them during working hours, you will get one-to-one support services.
I wish you all the best.
Best Regards,
Mitchell | Microsoft Community Support Specialist