On Feb 6, 9:32*am, John Fields wrote:
On 6 Feb 2009 08:47:28 GMT, Jasen Betts wrote:

On 2009-02-02, John wrote:
I would like to change the led's in a old pc I recovered amber=power
green=hd from there factory color to different colors like blue and super
red led's.

I use to play electronic hobbies years ago so I’m concerned that if I
just solder *the defferent color led’s to the leads *I might fry
something.

powersupply for the existing LEDs is most probably 5V through a series
resistor, so just replacing the leds should work. *the new leds may not
light to full brightness but will probably look good none-the-less.
There's no risk of damage to the PC by this modification as long as you
take due care.

---
Bad advice.

He needs to _know_ what the supply voltage is and the Vf and If of the
LEDs he wants to use before he can proceed with the modification
intelligently.

JF *

Actually it was good advice. They are current limited already, within
the typical sub-20mA range as with any other 100mW encapsulated LED.
This is a necessary design parameter for motherboards. You can blindly
grab a similar looking LED and hook it up to any motherboard without
issue, and indeed that is exactly what happens when you install your
choice of motherboard into a computer case.

The intelligent data collection choice is significant if a mistake
would take a great deal of time or expense if things went wrong, which
it won't, or if there was nothing yet known about motherboard
circuitry, which there is.