PSU quiet mod

Hey there,
I'm on a quest to quieten my PC, and have decided that my PSU is making the most noise of all my components. It's an Enermax EG375AX-VE Noisetaker 370w. I'm contemplating opening it up and changing the fans for <25Db ones, but i've never opened a PSU before and have always been wary of it due to the dire warnings on them :undecided - is it really that dangerous to it's health? Can't I just unplug the current fans and replace them in the same sockets with silent ones or will it kill the whole thing? Any advice much appreciated

Unless you are qualifyed electricion i would NOT do it. Even after disconnecting the PSU holds ALOT of charge (enough to kill you)

Extremely dangerous, they can hold power for a long time, one slip and you will be spark out on the floor for a few hours, if you re lucky.

Sensible warnings but I believe if you disconnect the PSU and leave it plugged in but switched off at the wall for a few days before opening it all the capacitors will have discharged. Not that I've modified a PSU myself but I've fixed the electrics in my washing machine following that principle and that's something like 1300W :mrgreen:

I don't know about that specific PSU but the reason it's loud could be because the fan is not temperature controlled, or it's inefficient and so needs more cooling than you might expect. If you swap the fan for 'quiet' one then either of the following scenarios would result:

1. It is of the variety with a built in resistor/thermistor that causes it to spin slowly and shift less air. You PSU could overheat and pop.

2. It does not throttle the voltage but is quiet on the basis of having high quality bearings - but the controller in the PSU will then spin it at exactly the same speed as before creating as much air (if not bearing) noise.

So you will either:

a) Electrocute yourself (most likely destroying the PSU too)
b) Cause your PSU to overheat and fail.
c) Not achieve a noticeable reduction in noise
d) Be fine and delighted with the results.

I'd just buy a new PSU if I were you!!! :)

I've opened up a PSU to change the fans before, and found three things;
1) I didn't die (though I was probably lucky)
2) The fan was odd dimensions (like 78mm ish), so a new one would require some filing.
3) It was not one you could just unplug, you would have to rip out the old fan wires and solder the new ones in.

So, IMHO, it's not worth it.

Though it could all be different for your own PSU.

I didn't realise that PSU's held charge for that long. I could've killed myself at work a few months ago. I swapped a fan over as it stopped spinning. Think I'll make a mental note of that, not going to do it anymore, think my life is worth a little more than &#163;20!!

I've modded a few psu's and fortunately Thank God I'm still ok.

To discharge

I remove the psu from case (this is very important :) )
Bend a paper clip and put ends into the pins connecting black and green wires
Switch psu on the back (making sure it's not connected to mains)

I've stuck with the above, although some people recommend unplugging from the mains and then switching off and on the button on the back of the psu.

Forton's I've modded have been hardwired. HEC psu haven't been hardwired.

I broke the two pin connector in a Seasonic Tornado :mad: so now the fan is connected to a Fanmate 2 and running at reduced speed.

If you really want to open up the PSU, then get a good multimeter and measure the residual voltage across the large smoothing caps on the mains input side. Unplgging the PSU and pressing the PC on button will discharge the components (although there may be a bit left in the interference filter (if fitted) on the mains input). But ALWAYS, ALWAYS check first - don't leave it to chance. And if you don't understand any part of this post, DON'T DO IT! (And if you do - its at your own risk!)

i changed a fan in shuttle psu, was quite easy, and didnt die at all :) just be carefull

I'd probably just buy a new PSU. A good quality 350W-400W will cost between £25-£40

I changed many many fans, and opened countless number of PSU, and i'm still alive :D. Just do watever you know to discharge the PSU, and use as much insulation as possible, you shouldn't die anytime soon.

Capacitors are strange beasts, charge them up and they stay charged for days (maybe even weeks depending on type) Short them out and they appear discharcged, but they still hold a resudual charge! Be very careful! I have blown chunks out of a screwdriver on many occasions even after discharging a cap!

I admit, theres not a great danger to your life, but there is a danger, a belt from a cap can leave you seeing stars for a while. My thumb swelled up to twice its size after a nasty belt of a cap! The real danger comes from screwing something up while you are modding the psu which MAY inadvetently live up your case with 230v AC, now that WILL kill you and anyone else who comes into contact with it! (Oh and it will fry your puter too!")

My advice as an electronics engineer is to steer well clear of anything with "danger 230v" or "no user servicable parts inside" printed on them.

I'm with Gfish, how much is your life worth!

I am another PSU mod survivor: the degree in electronics was useful, but wearing leather gloves may have helped :)

If you are after low noise then something modern with a single 120mm fan has to be the way to go. I have an Enermax noise-taker, next to a new Akasa PaxPower powered PC. The Akasa is _soo_ much quieter.

Altering the airflow around the inside of a PSU with slower/quieter fans would worry me too. Have seen enough PSUs go loud & crispy for one lifetime!

BTW, I went for switching off at the wall whilst the PC was turned on (BIOS screen ISTR) to get most of the energy out of my PSU. Even then, I did the soldering wearing leather gloves.

Quote:

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Originally Posted by DanceswithUnix

I am another PSU mod survivor: the degree in electronics was useful, but wearing leather gloves may have helped :)

If you are after low noise then something modern with a single 120mm fan has to be the way to go. I have an Enermax noise-taker, next to a new Akasa PaxPower powered PC. The Akasa is _soo_ much quieter.

Altering the airflow around the inside of a PSU with slower/quieter fans would worry me too. Have seen enough PSUs go loud & crispy for one lifetime!

BTW, I went for switching off at the wall whilst the PC was turned on (BIOS screen ISTR) to get most of the energy out of my PSU. Even then, I did the soldering wearing leather gloves.

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Did you actually suffer an electric shock or are you thinking you would have if you hadn't worn the gloves?