My Computer simply will not come on. There is no light, no sound, nothing is happening...

Don't worry, it may still be ok.

When there are power spikes or other problems with power the ATX power supplies in most new computers have a PG or Power Good signal which they send to the motherboard to indicate to the system that the power is up and ready to go. In cases where the power goes off and on very quickly, or in conditions of brownouts, this feature may simply be confused, and it can cause the machine to fail to boot or even light up when the power switch is pressed.

To fix it... remove your power cord from the wall for about 5 mins. The length of time may not need to be that long but 5 mins should give the power supply plenty of time to reset itself. After the 5 min wait, plug the system back in and try again. It should come on.

To avoid this problem in the future you should get a battery backup for you computer system.

If this fix fails to get your computer running you may need to replace the power supply.