|  | 8.10 | Network Power Supply Issues: Power Line Problems
| 8.10.2 | Normal mode and common mode
Normal mode problems do not, ordinarily, pose a hazard to you or to your computer. This is because they are usually intercepted by a computer's power supply, an uninterruptible power supply, or an AC power line filter. Common mode problems, on the other hand, can go directly to a computer's chassis without an intervening filter. Therefore they can do more damage to data signals than normal mode problems. In addition, they are harder to detect.