Pulling Power

[OUberLord]

This is a fairly simple problem, but I was hoping for some second opinions. At work here we have a few switches with bad fans. Long story short the 5v fans that are needed are $7 each, while the 12v ones we have on hand probably cost us a couple quarters but wouldn't get enough juice from the fan terminals to operate.

The power supply in all switches use the standard pinblock connector like you find on all ATX motherboards, only slightly shorter so its about 18 pins. What is the best way to modify the switch so that power can be pulled from the 12v leads on the pinblock? Score the 12v wire above the block to expose the copper and solder there, then seal?

[Butcher]

If it's like ATX then you can pop the pins out, solder to the back of them and push them back in - there's a fair bit of space around them. If the fit is tighter you're probably better off removing a small piece of insulation and soldering then sealing it up with electrical tape. As an alternative you could solder a new wire directly onto the board in the PSU of the switch (would be a bit tidier).
Don't forget to check with a DMM which wire is actually the +12V and ground!

[Steve]

Butcher is right. If you put a pin or something into the connector you can prise the connector out, and yes, check which is 12V.

[OUberLord]

Oh of course, I mean it "looks" like it follows the standard yellow, red, and black wire color scheme but I'll be double checking everything out first just to be sure. So those pins just pop out? Man, thatll make things way too easy, thanks for the tip. Ill be trying that later today.

Addendum:
Yeah, they pop right out, heh. Thanks again for the tip.

[SilentDeath]

As you say the switch is mainly 5v.. you should check the PSU will have enough amperage on it for the fans AND whatever else it might use 12v for.

The fans should run fine from 6.5v+ so it doesnt need to be exactly 12v.

Easyer than fiddling with pins would be to cut the cable, and have a 3way solder joint, covered in heatshrink it will look tidyer.