made my pc but its not silent!

reeds · Post by **reeds** » Wed Dec 24, 2008 6:35 am

Hi guys, the PC I put together is far from silent -- the fan is very loud. I can hear it all the way across the room. The case is an Antec Solo with the exhaust fan replaced with a Noctua NF-P12. This is running at about 900 rpm (5V). There are no other fans in the system. The graphics card is passive and CPU heatsink is passive too. The PSU is a Silverstone Night Jar (Silent apart from electrical noice buzz when you put your ear to it). Any tips to sort this out?I'm thinking of replacing the fan with a Noctua NF-S12 -- This one doesnt have the vortex notches on the blade and will run at 600 rpm. Do you think that will solve it? Thanks.

frenchie · Post by **frenchie** » Wed Dec 24, 2008 7:34 am

I also own an NF-P12 and I'd say this is NOT the source of noise in your system, especially at 5V !!! Those things are inaudible. Now it's possible that you have a faulty unit, so I'd RMA the fan and see what happens.

yamahaSHO · Post by **yamahaSHO** » Wed Dec 24, 2008 7:54 am

frenchie wrote:I also own an NF-P12 and I'd say this is NOT the source of noise in your system, especially at 5V !!! Those things are inaudible. Now it's possible that you have a faulty unit, so I'd RMA the fan and see what happens.

I would disagree. I have two P-12's running in my HTPC and they howl like a biatch.

edh · Post by **edh** » Wed Dec 24, 2008 9:28 am

Can you post your full system specs?

Any fan running at 900rpm should be pretty quiet unless there's something seriously wrong with it. Have you tried stopping/disconnecting fans to tell if the noise changes?

What about the hard disk? It's possible your case is picking up some nasty vibrations from the disk. Try disconnecting the power from the hard disk and booting. It won't boot your OS obviously but it'll give you a noise comparison.

yamahaSHO · Post by **yamahaSHO** » Wed Dec 24, 2008 9:42 am

I'm POSITIVE it's not the hard disk and I'm POSITIVE it is the Noctua's. They made the same noise with the LNA and ULNA (currently using the LNA).

SPCR tested them and they were louder than the Antec TriCools.

edh · Post by **edh** » Thu Dec 25, 2008 8:02 am

yamahaSHO wrote:They made the same noise with the LNA and ULNA (currently using the LNA).

Consider what you've just said there. It sounds the same at different speeds? If so you've just proved it's not the Noctuas.

Looking at your system, I would have far more issue with that standard nVIDIA cooler on a . Mine was far louder than any other fans I had, the reason why I replaced it as a planned part of my system build. I can't see why you'd leave one on if you're going to the trouble of spending money on a decent PSU and CPU cooling arrangement.

Anyway, we'd really need to see some specs to see the trouble area.

yamahaSHO · Post by **yamahaSHO** » Thu Dec 25, 2008 9:25 am

edh wrote:
yamahaSHO wrote:They made the same noise with the LNA and ULNA (currently using the LNA).
Consider what you've just said there. It sounds the same at different speeds? If so you've just proved it's not the Noctuas.

Seriously, I'm not an idiot. I've done plenty of testing and have taken into account EVERYTHING, however, one simple test to stop the fan PROVES that it's the Noctuas. Sorry d00d, my Noctua fans are the LOUDEST thing in my case, PERIOD.

edh wrote:
Looking at your system, I would have far more issue with that standard nVIDIA cooler on a . Mine was far louder than any other fans I had, the reason why I replaced it as a planned part of my system build. I can't see why you'd leave one on if you're going to the trouble of spending money on a decent PSU and CPU cooling arrangement.

Once you install the driver for the 9600GT, it's pretty much silent. My PSU is slightly louder than the video card due to the ball bearings.

edh wrote:
Anyway, we'd really need to see some specs to see the trouble area.

Search my posts, but it wouldn't do you any good. Simply turning off the fans completely has PROVEN the Noctua fans ARE the source of my noise.

reeds · Post by **reeds** » Thu Dec 25, 2008 4:16 pm

Hi guys, my specs are:

Case: Antec Solo with exhaust fan replaced with Noctua NF-P12 running at 940rpm (5V)
HD: WD 500 GB Caviar Green
Power: Silverstone Night Jar (Passive)
Chip: Intel Core 2 Duo 3Ghz
Heatsink: Noctua NH-U12P (no fan attached)
Graphics: Sparkle 9800GT (Passive)
Motherboard: EP45-DS3

There is only one fan. I put two NF-P12s in at first -- one for intake and one for exhaust but the system didnt seem to get that hot so I took the intake one out. But its loud. I can hear its woooooosh half a dozen meters away on the other side of the room. How do you get the fan to spin slower? Do I need a fan controller? The motherboard doesn't support dropping the voltage on 3 pin fans.

edh · Post by **edh** » Fri Dec 26, 2008 2:36 am

yamahaSHO wrote:Once you install the driver for the 9600GT, it's pretty much silent.

I disagree with you there. For me it has a horrid tonality to it.

Search my posts, but it wouldn't do you any good. Simply turning off the fans completely has PROVEN the Noctua fans ARE the source of my noise.

I was actually asking reeds for his specs before, but seeing how you both have the same fans in a similar position, one question: why have you used a P12 as an exhaust fan where there will be low resistance and therefore low back pressure? The P12 is intended for use in high back pressure. Noctua's own recommendation for such a set up would be the S12.

reeds wrote:How do you get the fan to spin slower? Do I need a fan controller? The motherboard doesn't support dropping the voltage on 3 pin fans.

940rpm is pretty fast for 5V. Some 120mm fans won't even turn at that voltage. It would be possible to 3.3V the fan using the 3.3V line from a SATA power cable. This is not clean and the fan may not start at this voltage.

You could also use a fan controller that sits in a drive bay or an expansion slot. This will just give you a simple manual control over it. I don't particularly like these things.

If the header on the mobo is a PWM header you could also use a PWM to DC adaptor. I have one of these:
http://www.paqt.co.uk/store/index.php?a ... roductId=5

It allows the system to control the fan speed as it would for a PWM fan but with the added advantages that there is an adjuster on it to adjust the fan speed range and that it does not cause the nasty ticking noises that some PWM fans make. It also still provides the RPM data.

yamahaSHO · Post by **yamahaSHO** » Fri Dec 26, 2008 6:20 am

edh wrote:
yamahaSHO wrote:Once you install the driver for the 9600GT, it's pretty much silent.
I disagree with you there. For me it has a horrid tonality to it.

MY fan is silent. Absolutely NO tonal quality what-so-ever.

Search my posts, but it wouldn't do you any good. Simply turning off the fans completely has PROVEN the Noctua fans ARE the source of my noise.

edh wrote: I was actually asking reeds for his specs before, but seeing how you both have the same fans in a similar position, one question: why have you used a P12 as an exhaust fan where there will be low resistance and therefore low back pressure? The P12 is intended for use in high back pressure. Noctua's own recommendation for such a set up would be the S12.

The P12's are suppsedly better with resistance, but they're not that great. Just because it is an exhaust fan doesn't mean it will have little resistance... Not sure why you would think the intake is the 'restrictive' fan. Resistance goes both ways.

They're an over-priced fan with a decent bearing. I've got SlipStreams in everything else now (even my Xbox 360) and they are the quietest fan I've used at a given air flow.

edh · Post by **edh** » Fri Dec 26, 2008 6:34 am

yamahaSHO wrote:The P12's are suppsedly better with resistance, but they're not that great.

They are aimed at shifting more air under a higher back pressure, nothing to do with noise level. They are louder than the S12's and always will be.

yamahaSHO wrote:Just because it is an exhaust fan doesn't mean it will have little resistance... Not sure why you would think the intake is the 'restrictive' fan. Resistance goes both ways.

Both intake and exhaust will be lower resistance compared to use on a heatsink or other area with high resistance, that's what I was getting at. At no point did I say that an intake would have higher resistance. I have a positive pressure system and I'd certainly use the S12 out of choice over a P12.

Resistance does go both ways but back pressure is specific to one. If you have more resistance behind the fan, a higher static pressure will be created.

From Noctua's site:

We principally recommend the NF-S12 for the following applications:
Case ventilation (with the exception of very restrictive fan grills, filters or significant obstruction to airflow)
CPU coolers with wide fin-spacing
Water-cooling radiators with wide fin-spacing
All applications where minimum noise emission has first priority

We principally recommend the NF-P12 for the following applications:
CPU coolers with tight fin-spacing
Water-cooling radiators with tight fin-spacing
Power supplies
Storage solutions
Cases with very restrictive fan grills and filters
All applications with significant obstruction to airflow

Unless you have an appallingly restrictive set of fan grilles, which from your photo doesn't look the case, use an S12 instead of a P12.

Post by **NeilBlanchard** » Fri Dec 26, 2008 5:55 pm

Hi,

I will second the recommendation for the Scythe SlipStream -- maybe the 800RPM would be enough, but definitely the 1200RPM.

Does the fan quiet down when you open the side of the case? Are you using a PWM controller?

frenchie · Post by **frenchie** » Tue Dec 30, 2008 10:14 am

If you're sure it's the fan, change it. Nothing really to add to that... It's just surprising that the Noctua is so noisy...

xan_user · Post by **xan_user** » Tue Dec 30, 2008 12:18 pm

any remote possibility that the noctuas in question might be fakes or knockoffs...?

-just a thought.

yamahaSHO · Post by **yamahaSHO** » Tue Dec 30, 2008 3:06 pm

Not a chance.

theycallmebruce · Post by **theycallmebruce** » Tue Dec 30, 2008 5:54 pm

Hey,

I'm not a fan guru, but I've built a PC based on fan recommendations here. I've never used the Noctuas, but I have Scythe S-Flexes (1600 RPM model slightly undervolted) and I find them very quiet, although still audible (I think you'd have to spin any fan very slowly not to hear it at all). The hard disk drive seems to be the loudest thing in my PC now.

Bruce.