Want to power LEDs on the 5v rail

[BarryD]

Got kinda bored so decided to start messing with some LEDs I got recently from trashed pcs. I've hooked them up to two 1.5v batteries and they work fine, got one that can produce green and orange light.

Anyway, to power these on a 5v rail I presume I need a resistor. My problem is I have no idea what kinda of resistor I need. Can someone tell me? and what markings on the resistor will tell me whether its the right one I need or not? I've all sorts of electronic things lying about I could get one from if I knew what to look for.

Thanks :)

[Dyck15]

Not sure if this is what you wanted, but here it is.

Its a little article on how to stick an LED into your molex connectors. It should give you some insight on how to hook them up either way.

http://www.themodfathers.jolt.co.uk/?page=&action=show&id=8643

[BarryD]

Cool thanks for that :) might try it sometime.

I found another article where there was a blurry photo of a resister he used (100 Ohm) to drop 2v from the 5v rail so it'd power the LED. From what I could make out, a 100 Ohm resistors colour bands are Gold, Red, Black and Brown in that order. I've found a few of those in a crappy old electronic radio I kept just for things like this, and i've already desoldered one.

Does it sound like I got the right one for a 100 Ohm resistor?

[Dyck15]

Ive personally never tried any of that stuff. I have a few ideas in my head of what I want to do, but I still have to research it all, specially resistors. :) Let me know if it works, I may use it in a mod or 2 of my own.

[BarryD]

I want to add a new case fan to my pc for extra video card cooling, so I want to hook it up to a switch so I need only have it on for gaming. Going to have an LED hooked up to the switch too. Just for the hell of it :)

[Dyck15]

Hehe, sounds cool.

One of my ideas was to stick a LED right beside the scroll wheel on my mouse and then when its dark it would illuminate the wheel :) I think it would be a cool effect. Only problem is, I have a wireless mouse, so it would drain my batteries more I would think. I may try it out on my other mouse, which is the same M$ mouse, but wired, and see how it looks.