Numlock LED on when computer is off

[Evoluter]

Does anyone have any idea why my numock LED indicator stays on sometimes when my computer is completely shutoff? When it occurs, it will stay on until I boot and shut off again. Does this indicate some kind of power problem?

 

[mgpaulus]

What kind of Power Supply / MoBo do you have? It sounds like you might have an ATX board, in which case, even though you think your system is completely powered down, it's really not. The only way to completely power down an ATX PowerSupply is to unplug it, or if you have a power switch on the back, to flip that. But not all Power Supplies have a cutoff switch on the back.

 

[stevewm]

Most motherboards today have a keyboard power on feature. Its normally activated by setting a jumper on the board and then going into the machine's BIOS and enabling it.

When the jumper is set it feeds power from the constant on +5v standby line (the standby line stays on as long as the computer is plugged in) into the keyboard to keep it powered otherwise it wouldn't be able to detect any keypresses.

Its not a indication of any problem. It doesn't hurt anything.

 

[Evoluter]

When it is in that state should it respond to me pressing the numlock key and caplocks etc? Cause it doesn't.

 

[stevewm]

Yes, thats normal as well. It should not respond to you pressing the NumLock key.

The status indicators on a keyboard are not controlled by the keyboard itself, they are controlled by the OS. Thats why it does not respond.

When you shut off the computer the keyboard will keep the light in whatever its last state was. So if the light was on when you shutdown the computer it will simply stay on. If you disable numlock before you shutdown the computer the light will stay off 😀