Early 2011 Macbook Pro slows down when on battery power
My early 2011 Macbook Pro works fine when the charger is plugged in, but it slows down significantly as soon as it is on battery power. I looked at activity monitor, and as soon as I unplug it, kernal_task jumps to 200%-1500% CPU and causes the usage rate to jump to around 98%. Any suggestions?
MacBook Pro (13-inch Early 2011), OS X El Capitan (10.11.3)