If it looks like an electrical storm brewing outside, shut the computer down and unplug both it and the surge protector. Also, keep the surge protector away from your feet, as it's easy to hit the off switch with a stray foot. Replace yours every 12-18 months. Modem phone lines need protection too. Ancient wiring, glitchy transformers, etc.
Heat is a major villain in the PC world.
The temperature inside your little box can easily reach over 100 degrees. Once the mercury starts spiking at around 110, you start frying components. As the searches progress, temperatures inch up, and alarms go off. And when you start adding peripheral devices, temps really climb. First, check the grate on your PC's power supply fan.