Power outage or black out likely won't cause damage to any hardware, but it can cause issue with your OS if the system isn't shutdown correctly. What normally follows power outages are power surges. This can damage anything plugged into an outlet. If you are having frequent power outages, you may want to look into whole house surge protector and make sure you have a quality surge protector for your computer equipment (tower, monitor, router/modem, etc..).
A UPS or Uninterruptible Power Supply will supply power for a short time during an outage and can prevent your PC for shutting down unexpectedly.
Agent Clarence G.
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