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Tristan
11-18-2005, 09:01 AM
Does anyone know of a method to supply power to LEDs when the computer is shut down?

I have installed an led behind my computer on/off switch and want to have it lit so that I can see it when I enter the darkened room. It is one of those single led "light canons".

Thanks.

crenn
11-18-2005, 09:08 AM
Use a resistor in combo nation of a LED on the 5v standby rail. That will do your task.

Tristan
11-18-2005, 09:23 AM
Thanks for the info. However, I have until now never heard of a "standby rail", and I suspect that in order to identify it I would need some tools that I likely don't have.

Can you point me in the direction of where to find out about this, as well as the resistor requirement? Thanks.

crenn
11-18-2005, 09:38 AM
IF I remember correctly, a resistor using a USB cable as a source of power is 330 Ohms. But I could be wrong, it will vary on the LED.

The standby rail is part of the main PSU connector. But where to it's location.... I wouldn't have a clue,

crazybillybob
11-18-2005, 10:54 AM
Remeber that the USB will only sink a Max of .5A (or 500mA). So I f you plan on using it for other things (mice, Drives, flash sticks...ETC) Don't connect to many LEDS. Ultra Brights will use up to 30mA each, Then you need to take into count the Device's draw as well.

Just helping you avoid an issue later.

Crazybillybo