CPU speed drops to 0.48GHz afer plugging charger

I have a Lenovo Yoga 500-15ibd laptop that I recently bought (used). Everything in it seems to be fine but whenever I plugin the charger it slows down. I looked at the task manager and I saw that as soon as I plugged in charger, the CPU speed goes to 0.48GHz and stays there no matter how I use laptop. Everything becomes extremely slow. As soon as I remove the charger, it goes back to 2.2+ GHz like it should. I looked at internet for the issue and tried following: All drivers are up to date. BIOS is up to date Some reported that the charger could be faulty, but I used another Lenovo charger (an

Question by ata on Super User, licensed CC BY-SA. We show a short excerpt and link to the original thread as credit.