Power light blinking (at regular intervals)

[Mirukai]

Hi All,

This is my first post! Yay! Anyway, I am having an issue where every four seconds, my Raspberry Pi 2 Model B's red power indicator blinks...

DISCLAIMER: I am installing phpBB3 on a highly overclocked Pi, using Apache2 as my server.

[Mirukai]

Oh, wait a minute, it stopped now I rebooted after installing phpBB. Will let you know if there are any changes.

[mahjongg]

power LED going of (for PI's later than PI B+) means the power voltage (5V +- 5%) dipped below 4.6V.

Most often the power cable is to blame, it has too much resistance. Use a better cable when problems persist.
Power problems will also trigger a small rainbow colored icon in the top right corner of the screen.