Thank you. You've just saved me a whole lot of time and expense on this problem. I restored the default power settings and that immediately solved the issue.Some of settings are probably incorrect for some reason. Restore the Power Options default settings first, and if that doesn't work, make sure the BIOS settings are correct. Also, try what happens when you remove the battery for about a minute (the computer should be turned off and the charger removed before).
If that also doesn't work, make sure your computer is running without a battery, that is, if you're only using a charger. Maybe there is something happened with charger and it can't give as much power as should. If charger works as should, Your laptop should work also without battery.