Has anyone replaced their PSU fan with a Noctua NF-P14 FLX Processor fan?

nocturnal1974 · 23 Nov 2011 at 18:56

Hello,

I want to replace my 140mm PSU fan with this particular fan. I was wondering had anyone else done this first as I am concerned about the starting voltage.

I have a similar thread going on overclockers and I know how to do the modification.

I'm trying to quieten my PC but maybe I should just buy an iMac!

Thanks

CinderzFTW · 23 Nov 2011 at 19:58

NEVER GET A ***** MAC!!!!!!!!!!!!! Do you need a slap???

Anyways, opening up your PSU for a start will void ANY warranty your have on it plus it is risky changing anything to do with your PSU as it is the only power input your system has. Screw it up and you can wave bye bye to your system with burn outs, power surges and possible total wipe out of your system and/or hardware.

Only do it IF you know what you are doing.

Replacing it will be tricky and I am not sure what the voltages of the PSU fans are. I suspect they are similar to normal fans, but my advice would be either leave it as it is, or get a new PSU with a newer, quieter fan on it.

Axleuk · 23 Nov 2011 at 20:30

CinderzFTW said:
NEVER GET A ***** MAC!!!!!!!!!!!!! Do you need a slap???

Anyways, opening up your PSU for a start will void ANY warranty your have on it plus it is risky changing anything to do with your PSU as it is the only power input your system has. Screw it up and you can wave bye bye to your system with burn outs, power surges and possible total wipe out of your system and/or hardware.

Only do it IF you know what you are doing.

Replacing it will be tricky and I am not sure what the voltages of the PSU fans are. I suspect they are similar to normal fans, but my advice would be either leave it as it is, or get a new PSU with a newer, quieter fan on it.

I agree - the PSU is the one thing I wouldn't contemplate modding. If the noise is that bad that you are thinking of opening it then indeed consider a replacement.

nocturnal1974 · 23 Nov 2011 at 20:42

Don't worry I know what I am doing. I am well used to this kind of thing and working with higher voltages >600+ Volts in audiophile valve power amplification and the like.

I don't care about the warranty. It is only a case of unplugging a 2-pin fan and plugging in another.

I was specifically asking had anyone used this particular model of Noctua fan for this purpose.

The danger situation when opening a power supply or such like is discharging a capacitor's energy through one arm whilst your other arm is earthed to the case ( yes the electricity makes a bridge through your chest (your heart) and can kill you ).

The golden rule is wear insulating gloves or work with one hand in your pocket!

I have touched live wires several times with 'one' hand and you feel a horrible throbbing dull pain. The throbbing comes from the mains frequency i.e. 50Hz

Tealc · 23 Nov 2011 at 21:13

Just remove the PSU cover and Start it up on the bench with a paperclip and use a multimeter to probe the existing fan's voltage. Armed with this you should be able to find the starting voltage of the Noctua. Some in depth PSU reviews at SPCR actually already check this and put it as part of their reviews.

Not many people modify their PSUs in this way it seems.

nocturnal1974 · 23 Nov 2011 at 21:46

Tealc said:
Just remove the PSU cover and Start it up on the bench with a paperclip and use a multimeter to probe the existing fan's voltage. Armed with this you should be able to find the starting voltage of the Noctua. Some in depth PSU reviews at SPCR actually already check this and put it as part of their reviews.

Not many people modify their PSUs in this way it seems.

Tealc do you mean run the PSU disconnected from the computer or connected? The PSU fan spins up within seconds of activating the power-on switch.

I would love to have the money to buy a Seasonic ( or similar ) semi- or passive PSU but these are £140. I'd say it would be well worth the money and maybe I should piggy bank the money instead of buying expensive fans for a PSU that isn't inherently designed for quietness despite it's title ( but thats marketing for you... aka. StealthXstream ).

And there is no such thing as a silent fan!

CinderzFTW · 23 Nov 2011 at 21:46

Axleuk said:
I agree - the PSU is the one thing I wouldn't contemplate modding. If the noise is that bad that you are thinking of opening it then indeed consider a replacement.

+1

Tealc · 23 Nov 2011 at 22:11

Ignore the naysayers. PSU modifications aren't as scary as some would have you believe.

Yes I do mean take it out of the PC, although it's not necessary I suppose. What you want is to trip the PSU and have it start up so you can probe the fan connector for it's lowest voltage with minimal load. In fact a couple of hard drives loading the PsU might help so just disconnect the aTX, EpS12v and any PCI-e connectors.

I fan nodded my first PSU without removing it fully. I just undid the screws and popped it out the side of my case and did the swap, and I had to cut and solder the fan in.

I'm not entirely sure whether a Noctua is the perfect PSU fan but 140mm sizes aren't as common as 120mm so options are limited, and the cost is quite high for a fan.

CinderzFTW · 23 Nov 2011 at 22:13

Tealc said:
Ignore the naysayers. PSU modifications aren't as scary as some would have you believe.

Yes I do mean take it out of the PC, although it's not necessary I suppose. What you want is to trip the PSU and have it start up so you can probe the fan connector for it's lowest voltage with minimal load. In fact a couple of hard drives loading the PsU might help so just disconnect the aTX, EpS12v and any PCI-e connectors.

I fan nodded my first PSU without removing it fully. I just undid the screws and popped it out the side of my case and did the swap, and I had to cut and solder the fan in.

tbh dude, some people may be able to do this, but the majority cannot...

doing this can screw your system over in the long run...

it will void any warranty you have on it for starters

my advice is just buy a newer psu that will serve you well for a year or two...

if you screw your system over, don't come running and crying to us for help... PSU modification is something that shouldn't be done!

nocturnal1974 · 24 Nov 2011 at 02:06

CinderzFTW said:
tbh dude, some people may be able to do this, but the majority cannot...

doing this can screw your system over in the long run...

it will void any warranty you have on it for starters

my advice is just buy a newer psu that will serve you well for a year or two...

if you screw your system over, don't come running and crying to us for help... PSU modification is something that shouldn't be done!

Its not changing the timing belt on your car! Some people are afraid to change a wheel

This is changing a fan, I would build a PSU from scratch given the PCB and all the components.

Its like anything, only do it if you know what you were at.

I'll have to measure the voltages as Tealc says, I have a multimeter, that says it all.

I'm not sure the Noctua is the perfect fan for a power supply, I was considering a Be quiet! Silent Wings USC 140mm fan as this is what is used in their top of the range power supplies I.e. must be suitable for this purpose!

http://www.overclockers.co.uk/showproduct.php?prodid=CA-045-BQ&groupid=701&catid=123&subcat=1083

Ciao, will do this when I come back from holidays and let you know how it went...

Zapp! haha

Tealc · 24 Nov 2011 at 02:38

Yes I'd be happier with the Bequiet too. It's the same basic reason I went for Magma as that's used in Enermax PSUs.

I'd quite happily build, modify or change the components in my PSU if there were some benefit, or if something had failed and I knew what had failed. I just don't understand people's reluctance to get their hands dirty in a PSU when they are mire than happy to modify motherboards, cases, coolers in the name of individuality and just leave their PSU at stock. The only thing that can go bad with fan swaps is a fan failure, polarity issues, insufficient airflow. PSUs are generally built with overcompensating fans for systems with no exhausts. In a proper system with normal exhausts, or a separate chamber like mime, or facing down to a vent the fan is spinning too fast and can safely be r

nocturnal1974 · 24 Nov 2011 at 02:39

I forgot to say I replaced fans in PSU's years ago when 80mm was the normal specification. Back then ( circa year 2000 ) Papst made the best fans and I can remember ordering 3 of them around £12 each. I still have an unused one in a box I found recently.

And I wouldn't recommend Joe public to work on PS Units unless they had electronics experience.

I did electronics at school, Uni and then as a hobby primarily with hi-fi separates ( replacing transformers with toroidal transformers, building valve amplifiers and Digital to Analogue Converters etc. ).

I think I'll ebay the Papst and look for the other ones to flog. I see they are £33 each now!!! :cool:

Cash In The Attic!

nocturnal1974 · 24 Nov 2011 at 03:00

Tealc said:
Yes I'd be happier with the Bequiet too. It's the same basic reason I went for Magma as that's used in Enermax PSUs.

I'd quite happily build, modify or change the components in my PSU if there were some benefit, or if something had failed and I knew what had failed. I just don't understand people's reluctance to get their hands dirty in a PSU when they are mire than happy to modify motherboards, cases, coolers in the name of individuality and just leave their PSU at stock. The only thing that can go bad with fan swaps is a fan failure, polarity issues, insufficient airflow. PSUs are generally built with overcompensating fans for systems with no exhausts. In a proper system with normal exhausts, or a separate chamber like mime, or facing down to a vent the fan is spinning too fast and can safely be r

Well currently the air blowing out of my PSU vent is cool. The case temp in the BIOS never goes above 34 Celsius. I'm only running Intel Core i3 530, 1TB & 2TB hard-disks ( modern ones which use about 12 Watts each ), 4GB RAM, a blu-ray drive, no discrete soundcard or graphics card ( although I'm getting the AMD 7850 when it arrives next year). I also have 1 120mm CoolerMaster exhaust fan now rotating at 700RPM (PWM controlled). I have the Arctic Freezer Pro CPU cooler which runs quiet all right.

Judging by your comments Tealc do I need a 60 CFM fan? I think I'll just have to bite the bullet and try the BeQuiet! fan. Apparently BeQuiet! Silent Wings can start at just over 3Volts for the 120mm version, the 140mm version may require a bit more torque to get it running though, check this out anyway...

http://www.youtube.com/watch?v=qwO5jTSuviU&feature=related

scottmuir424 · 24 Nov 2011 at 03:03

not a good idea playing about with the power supply unless ur qualified be careful

nocturnal1974 · 24 Nov 2011 at 03:13

another silent wings testing video...

http://www.youtube.com/watch?v=-s0KNyBuClI&feature=related

Tealc the BeQuiet website states 3.5V startup for the 140mm so no need to get the multimeter out!

http://www.be-quiet.net/be-quiet.net/index.php?StoryID=30&ProductID=52&websiteLang=en

Qualified at what? Read the above!

Any of you do the CompTia A+ certification? I did that too

Hotwired · 24 Nov 2011 at 04:16

You don't need a qualification to open your psu, void your warranty and change the fan.

Just know what capacitors look like, remember they can hold charge and give you a painful shock and don't mess about with any other components or wires than the wires needed to change the fan.

You're likely to need to unsolder the original fan wires then solder in the new fan wires. Make sure the polarity is correct and you're done.

Tealc · 24 Nov 2011 at 08:32

Judging by your comments Tealc do I need a 60 CFM fan?

Your mileage may be different to mine as you have a different PSU. What I did was buy a PC thermometer from China, stick it in my case next to PSU intake and measure and then did the same just at the rear of the PSU exhaust. I did a Prime95/Furmarking burn test to get my maximum power draw and then compared temperatures. With stock fan the difference was a few degrees and now with custom fan it's a degree and a half more again. So I've sacrificed overall cooling for quietness. My stock fan was a >2000 rpm screamer while yours sounds as if it's far more quiet to begin with. You can probably drop the CFM by 20% or so if you have good airflow. Some SPCR users get away with very slow fans in their PSUs and seem to be getting away with it.

The thing now is that I am unsure what would happen if I used the full wattage of my PSU. I suspect it'd be ok for the reasons mentioned above but nevertheless I will have to monitor temps again if I add something significant to my PC, which is unlikely as my graphics cooler takes up four slots and doesn't really permit crossfire.

nocturnal1974 · 24 Nov 2011 at 16:54

Tealc said:
The thing now is that I am unsure what would happen if I used the full wattage of my PSU. I suspect it'd be ok for the reasons mentioned above but nevertheless I will have to monitor temps again if I add something significant to my PC, which is unlikely as my graphics cooler takes up four slots and doesn't really permit crossfire.

4 slots? what cooler is that? I am looking forward to getting a graphics card except for the added noise from the fan. I want the new 7850 card when it arrives. It will dissipate 90Watts max and I would love to get a quiet cooler for it or a passive cooler.

Tealc · 24 Nov 2011 at 18:30

Its the Thermalright Shaman, thread about it here. Probably overkill for a 90W card though, but with semi-decent case airflow over the heatsink it probably could be run passive, or at least very slow fan. Even on a 200+w 6950 it's sub 1000rpm.

nocturnal1974 · 17 Dec 2011 at 09:53

Well now have the bequiet! Silent Wings USC 140mm installed and I have to say is a brilliant job.

This has been a fantastic upgrade. I cannot hear the PSU at all. This shows up the hard disks and CPU fan a bit more now, so now have further work to try and silence those also!

The bequiet fan is a quality bit of kit, forget your Noctua!