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I Hacked a PSU Answered

So I replaced the cheap power supply on my Compaq so I could upgrade my video card. Anyways I'm left over with this 200W PSU and I have no use for it. I opened it up and I see components galore and a 80 MM fan. There is also a bridge rectifier and, some really big transformers, and two giant blue capacitors @ 200v, 470uF. Do I have to remove the PCB to discharge the caps before I start salvaging or is there a better spot. The Chinese that made it also made use of a lot of white hot glue. And the soldering on the PCB just looks plain bad. You guys have any thoughts of what I could do with it? Besides the lab powersupply instructable?

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treg (author)2008-09-08

>really big transformers

In a switching power supply ? I'm not specialist of power supplies, but the one I open never hade any huge transformer.

>If powered it with 12v instead of 5 would that damage it ?

No, it is common practice to undevolt fans when you don't need a big airflow, because 1/2 fan speed = 1/4 fan noise, and 12V fan are standard, which means it is cheaper to buy 12V and undervolt it than to buy a slow / low noise 5V fan. So has been built to run at 12V, if that is what the sitcker says.

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emuman4evr (author)treg2008-09-09

I rewired my expansion slot fan today. Its pumping out a lot more air and there is a slight noise like there is a piece of gravel in the fan but I guess that is normal. Shortly after I started my comp there was a really loud fan that turned on then stopped. I guess its my video card. Not much increase in noise, just the sound of air being wooshed out of my comp.

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tech-king (author)2008-08-27

yes! 1) no, you can discharge the caps by leaving the fan plugged in and jumpering the green and black wires in the mobo power cable (atx 20+4). you can: auxillar psu for pc use it to power a car fridge indoors projects that need 12 and 5 volts, like tank battles.

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emuman4evr (author)tech-king2008-08-27

I noticed the fan is rated for 12v but its only being powered with 5v. I noticed the same thing for my expansion slot fan also. If powered it with 12v instead of 5 would that damage it ?

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westfw (author)tech-king2008-09-08

Sometimes this is done to cut down on noise - a 12V fan at 5V is cheaper and similar in air-flow to a special "low noise" 5V fan... (or something.) As for "really big transformers" - kids today! They don't know what a "really big transformer" looks like...

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