I hear thunder, and the light in my office goes black for maybe a tenth of a second. I have 3 PCs switched on, and none of them even blinks. Guess what gives trouble? My Ethernet switch. Even without a storm going on, it does this maybe once or twice a year: I can tell itâ€™s in a wedged state, because the status lights are stuck unblinking, showing an impossible combination. Power-cycle it, and itâ€™s back to normal, and my office connectivity is restored.