I am facing this weird problem with my Windows 7 Dell laptop (Core i5, 8 GB ram). The problem starts when every time I disconnect the power cable and use the laptop in battery for a while (lets say half an hour) then reconnect the power cable.
After connecting the power cable back suddenly every process become CPU hungry and all of them tries to take as much CPU as they can, no matter what they are doing! Even the task manager takes about 17-20% percent CPU!
If I kill some process/application to free up CPU use, some other process take up the free CPU, so the CPU use remain in constant 100% use. Only way out for me is to restart the Windows. I am wondering the reason of this kind of weird behavior, Is there anyone faces something similar to this? Is there any idea how to track down the reason?