Power LED doesn't light up

Hi,

Does the computer turn on and work OK and it is only the Power LED that does not light up or doesn't the computer even start?

If the computer turns on and works OK but it is only the Power LED that is the problem, check that Power LED cable wires that may be in the Front Panel I/O cable are securely connected to the header pins on the motherboard.

There should be a set of Front Panel I/O header pins on the motherboard. These should include connections for the Power button, the Power LED and the HDD LED

It should be printed on the motherboard as to what the header pins are used for and how the cables are connected e.g. +ve PWR LED , +ve HDD LED and PWR for the power button