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[neostar63]

What would be the maximum number of leds one could run off of a typical computer power supply. The power supply would only be used to power the leds nothing else. It wouldn't even be in a computer. It would be between 350 and 450watts. If anyone could recommend a place to buy a couple hundred amber leds on the cheap that would be helpful too.

[Dave303]

It comes down to what is the PSU rated at ...

I seen most that share 35A between the 2 leads for HDD / CDROM and what not, and ones as low as 11A for the 2 rails. The it comes down to what are the LED radted at.. and so on.

[neostar63]

well most leds i have looked are rated for around 2mA. So it could range anywhere from 11 to 35A. That is probably enought either way i go.

[blafrisch]

Well... lets just assume that you are buying a cheap POS 400W PSU and you are only running the LEDs on the 12V rail.  Newegg's cheapest 400W PSU has a 20A 12V rail which is about 240W.  An LED will typically use about 20-30mA and amber ones generally operate at about 2.1V.

So doing some simple math...
240W / 2.1V = ~114A / 30mA = ~3809 LEDs
(I may not have done this right, but I'm pretty sure I did)

Now this assumes near ideal conditions and that you know what you are doing.  In other words, you should be able to get a lot of LEDs as long as you have some clue what you are doing.



May I ask why?

[Vicarious]

enough to light up your house lampoons stye for christmas

there's alot of juice in PSUs (some can be 1000W+) and LEDs use like 1.5mA heh we all want to know what crazy idea you have planned...

[neostar63]

the idea is to make a chandelier. its going to be pretty sweet. It is going to be made out of bottles, the color of the leds should give away what kind of bottles. I am hoping that I have enough time after to work to start something before school starts again. There will be many a picture once this is started.

[blafrisch]

Mmm... beer

Beer + school =

[Skylined]

You're goign to have a hell of a soldering day if you plan to solder all the LEDs that a PSU can take.
Good luck, have fun.

[neostar63]

Its going to be a highlife chandlier. Yeah its going to be alot of soldering, only like 600 leds or something like that. I just need to figure out how to suspend the bottles.

[blafrisch]

Drill through the top of the bottle (very carefully) and use chain and run the wire through the chain like they do with most suspended lights.