changing PSU fan, how?

Just for the kick of it, I'd like to change the fan in my PSU.

Make it a bit quieter, and also adding more CFM's..

How do I do this? can it be done without soldering, and how hard is it to take a PSU apart?

Cheers, Flixotide

Getting PSU's apart isn't too difficult, there should be four tapered head screws on the top or around the side. Once they come out the top should lift off or slide over one of the ends.

When you get inside, how the fan is connected depends on the PSU maker. Some (like PCP&C) use connectors while less expensive PSU's solder the fan straight to the board.

Even if it does have a connector chances are you'll have to solder or crimp the wire to the fitting. The units I've seen that use connectors on the fan use a special size I haven't seen anywhere else. (Its about half the size of the motherboard three pin connector.)

You can use a crimp connector if you're not comfortable with a soldering iron.

One note about disassembling a PSU, and it is a big one, be very careful not to touch any of the capacitors when the PSU cover is removed. If they have a full charge and you brush against them, the shock can be fatal. Its a good idea to totally disconnect the PSU for at least 48 hours before you open to allow the caps to discharge. (The same applies if you ever get inside your monitor case.)

And speaking of fans-how do you like the Pabst's? I've seen them advertised in a couple of places, but I wanted to know how their noise and flow volume compared to Panaflo's before I ordered any.




BHD

Each PSU is different in how to take them apart take a good look at it and look at the seams to see what screws need to be removed to take the cover off don’t pry it apart either the fan wires are short on most and sometimes need to be taken off before the cover will come all the way off as for the fan connector some use the motherboard header some are soldered in and getting to them will void the warranty (if you have one still) on the PSU but the fan on most is a stock 80mm it just the header / connector I also agree with keeping it unplugged and to add a little to it turn it on with it still in the computer “but unplugged from the AC”

what i did was simply cut the the wires to the fan and tape up the ends. then i replaced the fan with a shiny new one. From there you can either join the fan to the wires you left in the psu, or (if it has a 4 pin adapter) plug it into the loop. simple.

BaldHeadedDork said:

And speaking of fans-how do you like the Pabst's? I've seen them advertised in a couple of places, but I wanted to know how their noise and flow volume compared to Panaflo's before I ordered any.

BHD

Click to expand...

Thanks for the info....

The Pabst fans are my preferred fans over zalman, sunon, thermaltake and enermax... but the difference is small.

The pabst one seem to have a noise frequency a tad lower than the others, and thus I find them less annoying, and it is the sole reason for my choice.

Cheers, Flixotide

It's not just the capacitors that can hold a high voltage charge. In many PSUs, the heatsink next to them may be connected directly to them and can have as much as 170VDC riding on it.

Be careful to not let any wires become pinched or cut when reinstalling the cover, and because there are so many high voltage areas inside, I would be hesitant about just taping the ends of the wire together because tape comes loose. I would much rather use heatshrink, crimp connectors, or tiny wire nuts, and I would want the wires tied up so they can't possibly tangle in the fan. Nylon ties are good for holding wires this way.

Ugh.... seems to big a hazzle to do just for kicks.... I'll leave it be for now..

Cheers and thanks for the help though

Flixotide

how does one turn off the temp sensor in ps?

You can dischare capacitors and heatsinks next to them buy making a "ground connector" witch plugs into the outlet, then just touch the wire from the outlet with heatsinks and capacitor connectors to discharge them.

Not to thread jack, but how about 7volt modding a PSU fan? I've searched my pants off, and come up with nothing. Can anyone help me out?

I wouldn't discharge the capacitors to the ground of an AC outlet but just to the chassis, and I'd want a 10,000 ohm resistor in series to prevent excess current from damaging the capacitor or blowing a fuse.

Shorting the temperature sensor leads will make the fan go full blast (it's probably safer to use a 50-100 ohm resistor instead of a direct short, in case of a mistake), but finding the sensor is another matter. It could be attached to the heatsink (careful -- one heatsink may have potentially LETHAL high voltage on it), be next to it (Antec/ChannelWell), or even glued into the hole of one of those toroid coils. I've seen them labelled TH or THERM for 'thermistor' or NTC for Negative Temperature Coefficient. But those labels may also be for the surge reducton thermistor on the AC side, which you don't want to touch because of the high voltage on it. If the thermistor doesn't touch the heatsink, then making it touch it could speed up the fan (a bit of epoxy?).