Replace fan on PSU?

Mercutio · 29 Jul 2013 at 01:06

Right... I'm considering my options with a slightly noisey PSU (Antec 750 TP continuous).

I could get a new PSU, sell this, etc etc but it's actually a pretty solid power supply.

Looking here:

http://www.silentpcreview.com/article1067-page3.html

The fan is a regular 4 pin PWM based fan...

Surely I can find something better/quieter and go that route? I've never had an Antec PSU give me even the slightest issue dependency wise. What do we think would be a good replacement fan to use here if I was to go this route?

CreateNPlay · 29 Jul 2013 at 07:01

Mercutio said:
Right... I'm considering my options with a slightly noisey PSU (Antec 750 TP continuous).

I could get a new PSU, sell this, etc etc but it's actually a pretty solid power supply.

Looking here:

http://www.silentpcreview.com/article1067-page3.html

The fan is a regular 4 pin PWM based fan...

Surely I can find something better/quieter and go that route? I've never had an Antec PSU give me even the slightest issue dependency wise. What do we think would be a good replacement fan to use here if I was to go this route?

To be honest, it's not a good idea to open up a psu.

unleashed · 29 Jul 2013 at 07:44

CreateNPlay said:
To be honest, it's not a good idea to open up a psu.

Notwithstanding warranty issues etc. can you explain why it's not a good idea to open up a PSU?

UnworthyBean · 29 Jul 2013 at 08:03

unleashed said:
Notwithstanding warranty issues etc. can you explain why it's not a good idea to open up a PSU?

The capacitors can hold a deadly charge for a couple of weeks.

Saying that, I've opened up PSU's in the past and just made sure to stay away from everything. Make sure to drain the PSU and then leave it for a while. I'm still alive.

CreateNPlay · 29 Jul 2013 at 08:14

UnworthyBean said:
The capacitors can hold a deadly charge for a couple of weeks.

Saying that, I've opened up PSU's in the past and just made sure to stay away from everything. Make sure to drain the PSU and then leave it for a while. I'm still alive.

But as you said "Deadly", that's why don't bother. Just buy a better one.

Tealc · 29 Jul 2013 at 11:10

That particular PSU looks like a simple one to change the fan with.

As a precuation power down PC overnight and remove the power cord and jab the PC power button a few times. The first time you may see a few LEDs flicker and die.

In the morning jab the power button a few times to further discharge the primary capacitors.

To replace the fan.

1. Undo the screws.
2. Remove the bit with the fan in.
3. Don't touch anything, and that includes the heatsinks. Better to be safe.
4. Pull 4 pin connector off.
5. Cut off 4 pin connector 50mm from end of wire.
6. Get replacement 4 pin PWM fan and remove its connector.
7. Solder the wires together in the correct order, insulate.
8. Fit connector to PSU.
9. Close.
10. Profit.

I've had a several PSUs open and never had any trouble.

Seems a shame to bin a perfectly stable PSU just for a fan issue.

Mercutio · 30 Jul 2013 at 11:00

Aye, as an update, decided to leave it be. Spent about.... 4 hours trawling the internets for a fan that can match the one in the PSU. Seems to be a bit of a mission (85CFM, 3.4mm pressure for <38db).

The problem was the computer noise while the missus was sleeping but seems it was more a "get off the computer" excuse

As a side effect I've found that it seems most power supplies have a "ramp" on them around 50% (fan starts to be heard, often getting louder quite quickly). If you don't want a noisy PSU you have to go Gold rated or look at the bequiet ones for a slightly more modestly priced unit.

Tealc · 30 Jul 2013 at 12:12

It is usually ok to reduce the spec of the fan a bit. The PSU designer will usually design in a fan far faster than required just in case some muppet puts it in a system where it is the only exhaust fan and it therefore has to deal with heat from all components, not just itself.

As an example I downrated the fan I swapped in the last two PSUs by almost 1000RPM.

In my current PSU, a gold rated one, the stock fan was a 2,400RPM very noisy fan and I fitted a 1,500RPM quiet fan, yet the temperatures are fine and the fan speed never rises above 1,100RPM so clearly is not an issue. It's been running for over two years like this.

http://forums.overclockers.co.uk/showthread.php?t=18261286

Mercutio · 1 Aug 2013 at 10:16

That's worth knowing/being helped to realise. The case is probably transitioning to something with a closed loop on the CPU and the GPU + usual moderate airflow (quiet on the "cheap").
If it properly happens I'll stick a mini build log up as it will reference the zip tie approach on the GPU