Removing power supply fan, is it unsafe ?

PSUs: The source of DC power for all components in the PC & often a big noise source.

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gihad
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Removing power supply fan, is it unsafe ?

Post by gihad » Thu Sep 15, 2011 11:00 am

Hello all,

First of all I'm glad this website/forum exists, my family and friends have called me crazy for going through a lot trouble in order to make my computer silent. I now know that I'm not alone.

I built an HTPC an recorded a video about it: http://www.youtube.com/watch?v=FuiDSAg1l54

At first I thought the result was very good, but now I want to make it more silent.

My question is, is it safe to remove the fan inside the powersupply? It features a small fan and I think it's generating some unwanted noise.

It's a SilverStone SG05 case, it comes with a small 300W power suply, but I only have an I3-2100, a watercooler and a 5400rpm drive connected to it.

That HTPC also has a Seagate Barracuda Green, which I will be returning and getting a Western Digital Caviar Green.
Will the move from Seagate green to WD green make a difference ? Or do I need to go into something even more silent than the Western Digital Caviar Green ? Any suggestions ?

Thanks.

xan_user
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Re: Removing power supply fan, is it unsafe ?

Post by xan_user » Thu Sep 15, 2011 5:08 pm

WELCOME TO SPCR!

I would not remove the PSU fan. Maybe replace the fan (or psu) with better quality unit and/or under volt it. http://www.silentpcreview.com/article6-page1.html

Decoupling or suspending the drives from the case chassis is generally the preferred way to silence a spinning HDD.

kater
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Re: Removing power supply fan, is it unsafe ?

Post by kater » Thu Sep 15, 2011 10:23 pm

Yeah, agree with xan_user - swap the fan or undervolt it, but keep it running; if you choose to run it at lower RPM, make sure the PSU is not overly hot. Sure, your setup draws v v little power, but the PSU's heat should be taken care of, somehow. FSP PSUs are good quality, but this one is not particularly efficient and does generate some heat.
I'd suggest getting a quality 80mm fan (say, Noctua, NoiseBlocker, etc.) and running it via a mobo header at a constant 900-1100 rpm. This kind of speed should be both practically silent for your needs, and safe in terms of temperatures.

As for HDD noise - WD GP are quiet, sure, but far from silent. Still, if you put one in an HTPC and use the system just like most HTPCs are used, you won't hear the drive. Ii will be practically inaudible. HTPCs are usually at least 2-3 m away from where you sit watching something. Add to that the film's dialogues or noise, and your average, decent HTPC is virtually silent.

Love the Logitech mini keyboard - alas, it's so damn expensive it's probably as expensive as the innards of my HTPC.

And bring the Antec cooler's fan down - 1000 rpm for a 120mm fan is way too much in my book. The original fan in my PSU (Antec's custom PSU for NSK1380) ran at a minimum of 1000 rpm, even at super low load. It's now swapped for a quality Fander 120mm with manual rpm control, running at <700 rpm. Pure bliss. Sure, one a movie starts playing you would be hard pressed to really hear the 1000 rpm Antec, but I swapped it anyway.

quest_for_silence
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Re: Removing power supply fan, is it unsafe ?

Post by quest_for_silence » Fri Sep 16, 2011 3:04 am

gihad wrote:My question is, is it safe to remove the fan inside the powersupply? It features a small fan and I think it's generating some unwanted noise.

Generally speaking, it's unsafe and very likely it would lead to a premature PSU failure.

But perhaps the bad news is that, as far as I know, there isn't any SFX PSU which is really quiet, so I think you're stuck with it (or so about).

Well, first of all I would check where the noise come from: I would stop/disconnect the front fan, hear the noise level, and then (just for a few seconds) stop even the CPU fan (you may use a toothpick), in order to hear any noise difference. Just as a very personal bet, I think the front fan may be louder than the SFX PSU.

If you find out that the SFX PSU is the major noise source, I would check the PSU fan, if it's a 2 or 3 wires one: please take note that this inspection void the warranty.

Then, if it's a 3-wires, I would route the header to the mobo and slow down it by BIOS or SpeedFan (Windows). If it's possible.
While, if it's a 2-wires, you have to swap it with an about 1000rpm with fluid or ball bearing 3-wires one (a 4-wires PWM fan could also work in some cases), and then again reroute it on the mobo header.
You might route even to the original PSU header, but you may incurr in some startup issues (the fan might not spin at all, a tricky/risky scenario).
If your motherboard does not have any suitable fan header, you have to buy a rheobus (but I don't know where you can mount it on a SG05).

About the HDD, from a noise perspective, the Barracuda Green is generally outclassed by pretty much every low power desktop drive on the market, and it is about on par with some quiet 7200rpm desktop drives, as some 7K1000.
So a Samsung F4, an Hitachi 5K3000 or 5K1000.B, and the quoted WD Green should be noticeably preferable. You might also thin to susped it under the ODD.

Quieter than these, you have the SSD, but a 256Gb SSD is still a costly choice, not to mention the relatively low capacity.
Last option (but just for low-to-mid capacity) is a notebook drive enclosed in a SQD: double or triple the space with reference to the SSD, while the price is more than halved. But I don't know if it's really noticeably quieter than a WD Green, maybe suspended (while surely a notebook drive is less performing than it, according to benchmarks).
Last edited by quest_for_silence on Fri Sep 16, 2011 7:40 am, edited 1 time in total.

gihad
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Re: Removing power supply fan, is it unsafe ?

Post by gihad » Fri Sep 16, 2011 4:22 am

The 120mm fan at the front has been disabled since the beginning, I get 46 degrees on the CPU and about 40 degrees on the mobo when running prime95 for a long time.

I already did tests stopping the Noctua fan on the watercooler and the noise pratically didn't change, which leads me to believe it's the PSU fan and/or the HDD, I will first deal with the HDD by swapping it by the WD green and suspending it.

If It's not as good as I want I will deal with the powersupply fan, which I suspect is the problem. Also, the PSU fan is less than 80mm :/ it's a smaller then usual fan.

gihad
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Re: Removing power supply fan, is it unsafe ?

Post by gihad » Fri Sep 16, 2011 4:26 am

kater wrote: And bring the Antec cooler's fan down - 1000 rpm for a 120mm fan is way too much in my book.
I replaced that Antec fan on the side by a Noctua and I'm running it at 700rpm. It's almost silent.

kater
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Re: Removing power supply fan, is it unsafe ?

Post by kater » Fri Sep 16, 2011 4:46 am

It just occurred to me - the 80mm fan inside this PSU is a slim version. As in - not 20 mm thick, but only 15 mm. I'm pretty sure no regular 80 mm fan will fit inside.
Options:
- somehow connect it to a header on the mobo / molex / Fanmate,
- replace it with a good fan of choice installed externally - on "top" of the PSU, with the grill removed not to obstruct airflow; connect and run as you please.

quest_for_silence
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Re: Removing power supply fan, is it unsafe ?

Post by quest_for_silence » Fri Sep 16, 2011 7:36 am

kater wrote:- somehow connect it to a header on the mobo / molex / Fanmate

It's a 2-wires fan: he should go for a convenient molex, or adapter like the Zalman MC1 (I think that I've never used a 2-wires fan with a fanmate: does it work as usual?).
kater wrote:- replace it with a good fan of choice installed externally - on "top" of the PSU, with the grill removed not to obstruct airflow; connect and run as you please.

It could have not any useful clearance, as the PSU is right on top of the "keep-out-zone": which is, and how tall is the cold plate/pump?

kater
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Re: Removing power supply fan, is it unsafe ?

Post by kater » Fri Sep 16, 2011 10:51 am

If the OP (hello, you there?) chooses to connect the tiny 2-pin connector to a regular 3-pin header then I guess some bending or modding is in order. I have some tiny 40mm Scythe fans lying around, 2-pin originally, but they also have a 2-pin > 3-pin cable. A handy thing, but could be hard to get separately. Still, I don't think reusing the stock slim fan is the best option here.

I'd rather slap a good 80mm (regular thickness) outside the PSU. If you look closely around 6:40 mark, you can quite clearly see there's ample room under the PSU. Also, the PSU is not directly over the pump assembly. Anyway, I can't see how another 2 cm would block anything there. Also, a fan is not just a hunk of plastic - its moving arms would actually draw some air from around the CPU area. Not that it would matter much with such a beefy cooler on such a low-energy CPU ;)

gihad
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Re: Removing power supply fan, is it unsafe ?

Post by gihad » Fri Sep 16, 2011 1:13 pm

Hey guys, thanks a lot for the replies.
I tried to reply this morning but somehow my message didn't get posted.


I already bought a Western Digital Green to replaced the Seagate Green (still within return period), I will suspend it, hopefully this will help.

The 120mm fan at the front is not even running, To reduce noise I disabled it before recording the video and never touched it again. The only fans running in the system are the the Noctua on the side(attached to the radiator) and the PSU fan.

This PSU fan is weird, I think it's smaller than 80mm(not sure, I will measure again), I will probably buy a quiet 80mm and put it under the PSU. The Noctua fan came with 2 "12V resistors" to decrease current, I'm using one of them, I can probably use the other one for the new 80mm fan.

These are the 80mm fans available to me:
http://canadacomputers.com/advanced_sea ... filter_id=

Any recommendations ? Also, any recommendations on how to mount it "cleanly" under the PSU ?


Gihad.

kater
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Re: Removing power supply fan, is it unsafe ?

Post by kater » Fri Sep 16, 2011 11:42 pm

Your PSU fan is definitely an 80 mm one. Only thing is it's thinner - 15 mm, instead of the regular 25 mm*. So if you decide to buy a new one, most likely a regular one, you'd probably have to install it outside of the PSU. This is what I have in mind - see pic:

Image

Simply use regular fan screws or those rubber sticks that probably come with Noctua fans and you're done. Using one of the Noctua ULNA thingies is a good idea, but make sure your PSU fan starts reliably at lower voltage. I think you can safely run it at constant speed of at least 1000 rpm - it's not like your HTPC will be operating 24/7 under full load in a wooden shack with no AC in Florida ;)

As for your choice of fans I'd go with Nexus Real Silent - hi quality low noise fan, tested by SPCR. The AC fans are great too, but unusually thick - 34 mm. I don't think the Cooler Master Slim will be much better than your stock PSU fan.

As for connecting the Nexus you'd have to find the right balance of airflow and noise - either use a 7V or a 9V adapter. See the above test for RPM figures on each voltage. For any practical purposes a quality 80 mm fan spinning at 1000 RPM, inside a case located at least 1 m away, next to a WD GP, is practically silent.

* I previously stated a regular 80 mm is 20 mm thick - an obvious brainfart, as a regular one is 25 mm thick, just like regular 92 mm and 120 mm fans.

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Re: Removing power supply fan, is it unsafe ?

Post by SebRad » Sat Sep 17, 2011 2:56 am

Hi, I helped a friend silence his Antec Fusion based HTPC. It's a thinner Micro Fusion case but it has a TFX (or there abouts PSU) in it and the PSU fan very quickly became the major stumbling point.
So fan swap in order, take it apart and like you find, oh dear, the fan is 15mm not 25mm thick and no way a 25mm fan going to fit inside the PSU.
There is a vent in the chassie and some clearance between PSU and case like this:
Image

Basically we just cut out the orignal fan area completely to leave a hole in the PSU cover a 80mm fited nicely in to. Then made up some strips of bent metal to hold the fan half-in-half-out the PSU. The strips are bolted to the PSU cover and screwed to fan in normal way. Sorry no photos but here's my best "paint" graphic!
Image

Used thin aluminium strip for ease of working it, no strength required. Used a Panaflow L1A I had going spare and connected it to the original fan wireing so the PSU is still in control of it. Hopefully the greater depth of fan more-or-less makes up for the lower speed. As the Panaflo is a nice fan it's now dead quiet so a very sucessful mod :-)
Only got E5200 and onboard graphincs and single HDD so 50w idle 75w load (IIRC) so minimal load on PSU and should be just fine.

Hope this helps, Seb

gihad
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Re: Removing power supply fan, is it unsafe ?

Post by gihad » Sat Sep 17, 2011 5:41 am

Thanks for the reply.
kater wrote: As for your choice of fans I'd go with Nexus Real Silent - hi quality low noise fan, tested by SPCR.
My motherboard has "PWM", how about this one: http://canadacomputers.com/product_info ... _id=040015

Wouldn't that eliminate the need to undervolt the fan "physically" ? Or am I safer (for noise purposes) to go with the exact Nexus real silent model that was reviewed here ?

gihad
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Re: Removing power supply fan, is it unsafe ?

Post by gihad » Sat Sep 17, 2011 5:43 am

SebRad wrote:Hi, I helped a friend silence his Antec Fusion based HTPC. It's a thinner Micro Fusion case but it has a TFX (or there abouts PSU) in it and the PSU fan very quickly became the major stumbling point.
Those are good "schematics". I'm gonna try a simpler solution first, I wanna use the rubber things that came with my Noctua fan, my only concern is that it won't touch the bottom of the psu. but it will be very close.

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Re: Removing power supply fan, is it unsafe ?

Post by quest_for_silence » Sat Sep 17, 2011 6:31 am

gihad wrote:My motherboard has "PWM", how about this one: http://canadacomputers.com/product_info ... _id=040015

Please, avoid: it's not on par with its 3-wires cousin.
gihad wrote:Wouldn't that eliminate the need to undervolt the fan "physically" ? Or am I safer (for noise purposes) to go with the exact Nexus real silent model that was reviewed here ?
The Nexus is a good candidate, but it's a sleeve bearing one: you might have to change it in a year or two, as it's likely to develop bearing noise when in an horizontal mounting (as in the SG05).

IMHO you have to look for a 1000-1500rpm fluid bearing one, as the Scythe S-Flex or the Noctua R8.
If you want to go for a thinner model, you may ask to Sidewinder Computers (USA) for a San Ace or a Delta specialty.

Eventually, there's no need to undervolt phisically a fan unless you use some form of control (SpeedFan for mobo headers, or BIOS as seen on most of MSI or ASUS boards).

gihad
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Re: Removing power supply fan, is it unsafe ?

Post by gihad » Sun Sep 18, 2011 5:24 am

Hey guys, I did some more testing and I found out that the PSU fan is actually very quiet, I would even say silent. When I manually stop it from running I can't hear the difference and that's with the case open.
I added some eggs carton on the inside where the front fan use to be at and some on the outside between the fan wholes and the front panel, there are too many openings in this case.
I also suspended the new WD Green drive with elastics.

After all that I still get some noise, mostly a high pitched noise coming from the water-cooler pump (tac tac tac), but I can barely hear anything from sitting distance.

The way I suspended the WD Green with elastics put it in a non-horizontal position, it's tilted by 15 degrees in one direction an about 5 degrees in the other, is that a problem ? edit: this is not a problem.

It's probably time to stop this madness and enjoy my HTPC. :lol:

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