Howdy!

I'm new here. I recently started to read all the great reviews/articles on this and others sites

A month ago, when I started my build, I did very little research because I did not have as an objective overclocking or making a "silent" PC... but things change

So my components are not ideal, but in trying to get the most from what I have I would like some advice...

My machine is a i7-960 @ 3.84GHz 1.2375V. It runs reasonably quiet @ 35.3 dbA and not too hot -- 43.5C idle and 78C on Prime. My background noise in the room is 29.3 dbA and the ambient temp was 25.5C that day. All fans on low.

I'm looking to bring it to 4GHz, but not at the expense of making it more noisy.

I run a very quick trial earlier today. A first guess of 1.4V looked promising, but Prime brought my temps to 97-98 and I discontinued the test.

Here is my current set up:

i7-960 Bloomfield @ 3.84GHz 1.2375V
ASUS P6X58D-E
CORSAIR DOMINATOR (3 x 2GB) DDR3 1600 TR3X6G1600C8D
ZALMAN CNPS9900A LED
Antec Nine Hundred Two Black Steel ATX Mid Tower Computer Case
Extra Antec Tri-Cool fan on the side
XFX Black Edition XPS-850W-BES 850W
2 x ASUS Black 24X DVD+R
Koutech IO-RCM621 All-in-one USB Card Reader
Intel X25-M 80GB SSD
Logitech G500 10 Buttons Dual-mode Scroll Wheel Wired 5700 dpi Mouse
2 x XFX GeForce 8600GT Video Cards
4 x Western Digital Blue 250GB 7200 RPM in RAID 0+1

Here are my temps


Here are my dbA's at about 1m from the case


After some research I figure I would try the following:

1) Replace the Zalman (37C at the fins) with a Megahalems in a push (Noctua NF-P12) pull (Noctua NF-S12B FLX) configuration.

2) Replace the Antec back fan with a second Noctua NF-S12B FLX

3) Somehow add a small Noctua NF-R8 hovering over the memories (45C at the fins, 55C on the mobo left of the memory area)

4) Add a 4PST switch to turn off the HDD and front fans -- most of the time I only need the SSD. BTW, the HDD's run very cool at less than 30C, which is about the case temp.

5) Add Zener Diodes in series with the fans that remain to slow them down and make them quieter.

My main concern is: Would the Megahalems push/pull configuration be louder than my Zalman with the "quiet" resistor. If it would be any louder I would drop #1, #2 and #3 -- just do #4 and #5 and live with the i7-960 @ 3.84GHz.

Any ideas if I should give it a try?

I want to keep it air cooled, cuz adding water starts a whole new set of challenges

Any other ideas/recommendations?

Thanks!

While SATA can be hot swappable (meaning unplugged and plugged back in "on the fly") I would advise against using a power switch to control your second internal storage drive. Just to be safe, I would say you're safer putting in into an external enclosure and connecting it when you need it. eSATA is very fast, and should be just fine for this if you need the speed, otherwise USB is just as good at transferring files as anything else.

I do not think a push/pull system will give you any benefit over a single fan, simply because adding the second fan will add noise. Granted running them at lower voltage will mean less noise, I think it would be best to see where one fan gets you before ordering a second. The Prolimatech Megahalems is a massive and very good cooler. I doubt you will really need two fans on it to reach 4ghz, even silently with the correct choice of fan.

I would say that one of your main sources of heat is actually those two 8600GT's you have. Their heat must radiate to all other parts of the case, and to be perfectly honest, I'm sure they generate plenty. I would say suspending a fan to cool them off in the hard drive cage (or around it) might be the best option, after dropping those 4 extra hard drives into enclosures or some other place.

As for what really confuses me about the hard drives, you haven't really given a reason as to why you need them in RAID, much less 0+1. It's a lot of drives taking up space and heating up the air entering the system for everything else.

Also, I'm a little confused by what you're really aiming to do. If you drop all the Antec Tri-Cool fans, and go with a CPU fan, an exhaust fan, and one extra fan to cool the GPU's down, I think everything else should be set for good. I personally focus on minimizing heat from the source, so a large CPU heatsink with a 7v fan is more than enough to ensure the CPU is cool all day long. It will heat up under load, but as long as it's well within thermal spec, if my CPU reaches 60C, I'm not going to have a heart attack. My GPU is the same way, and those are the only major heat producers in my setup. I understand that you want to hit 4Ghz, and that you want it to stay cool, but thermal spec is important to pay attention to. Sure, keeping things below 40C at idle and below 70C at load is great, but an i7 wont do it quietly.

For you, the Megahalems will be a great upgrade, and will definitely get you running much cooler, but there are other options which may work out even better, such as the Noctua NH-D14, or even the Thermalright HR-02. The Zalman cooler you have isnt terrible, but it doesn't disperse the heat nearly as efficiently as other heatsinks do, and that's really what you should change if you're worried about temps. I would say that you're fine with the Megahalems, but as I said, start out with one fan, and see what the temps are like. It's entirely possibly that you're going to see temps that are right where you want them with a single fan, simply because the Megahalems cools so much more effectively than the Zalman you have now.

I would personally drop all the tri-cool fans, and just run an exhaust fan on the back, and maybe one on the top as well, simply because air pressure will feed your computer cooler air right where it needs to go at all times. I find intake fans with a front mesh panel give off more noise than they help with cooling.

In terms of what you own already however, the hard drives are probably causing a hum/vibration in the case, which is part of the noise, and the tri-cools are another part of the general noise. Lastly, while the Zalman isn't bad, it's just not a performance cooler, but it's capable of getting the job done, at the very least, better than the stock cooler. Swapping out the zalman is going to be your biggest change in temps. Changing fans will be your second biggest change in temps, and lowering the number of fans you have will be your first step towards silencing the rig, the second would be suspending those drives, or putting them into quiet drive modules, or even some external enclosures or a NAS enclosure.

Hi Bonestone.

Thanks a lot for your thoughtful post!

I can try to explain a couple of the choices...

The video cards -- the cards are almost 3 years old and were pilfered from my previous built. They are not expensive cards the one important thing they to do is to drive one 30" display at 2560x1600 and two 21" displays at 1600 x 1200. The main use for this machine is coding and having all that real estate on the screen is what "makes" the machine. The original card fans were replaced by "ZEROtherm GX810 2 Ball VGA Cooling" fans back in 2007, which seemed to be a good choice at the time. Given that new cards/coolers would probably set me back a pretty penny (not sure if they would produce less heat) I'll probably look into this part of the system last. They do run hot at 50-52C, but are reasonably quiet -- stopping their fans does not seem to change the noise signature of the system.

The hard drives -- I always do RAID 0 on my machines as twice this type of set up saved me major headaches. My previous system used 2x250GB and I had another 2x250GB in a drawer to replace any failing drive... Since 250GB is no longer sufficient I just reused the 4 disks and made it into a RAID 0+1 with 500GB usable. It is used for archiving photos, music, other files, as well as to backup the main SSD drive. They do not run hot at all. I'm planning on having it OFF most of the time. I would only flip the switch (a couple of times a week?) with the machine off.

That effectively eliminates the HDD's as they would be off 90% of the time.

I think the Noctua NH-D14 is a bit too big for my set up. I researched it and I would need to take the fins off the Corsair Dominator SIMMs and try to replace the thumbscrews of my video card fan assembly on the fist PCIE slot to make it more flush so that the NH-D14 can fit. It also seems that it would make the memory area a bit crowded and that is already running hot.

So I'm leaning towards the Megahalems, but with a single fan as you suggested. I'll probably try the Nexus since it seems to be the preferred choice here

I'll follow your advice and try to do away with the tri-cool's. In terms of fans I would have the 2 VGA coolers (have to have them with these cards, but they run very slowly), 1 Nexus on the Megahalems , 1 Nexus replacing the tri-cool in the back.

I'll try to lower the memory voltages which is something I'm running at "default" and is probably higher than it needs to be. I'll try to run without the top fan to see what temps I get. In general I got the message that fewer fans may be better if the air is flowing where it matters

I'll also do some research on a possible quiet replacement for the 200mm fan at the top of the case.

How does that sound? (pardon the pun)

So I placed the order

Did a lot more research on the suggested coolers: Noctua NH-D14, Thermalright HR-02, plus the Thermalright Silver Arrow. Almost went for each one of them at one time or another. In the end I decided to go with the Megahalems because, as you said, it is probably good enough to yield acceptable temps with a single quiet fan. It is also the least likely to have compatibility problems (not fitting).

I ended up getting the Noctua fans, mostly because the 2 places I normally shop at did not have the Nexus in stock. I got the NF-P12 for the CPU cooler and the NF-S12B-FLX to replace the case's back fan. Hoping to run them on the lower voltages. We will see how audible the whole thing gets

Fairly optimistic now. Even with the Zalman and fans on low it is running at 4GHz and 1.3V at 88C on Prime 95 -- and 48C on idle

With the Megahalems I should be able to run cooler and/or quieter and/or perhaps hit 4.1 or 4.2 GHz

Yeah!

Working from home today and I have been using the computer at 4GHz (and fans on low) without any problems. Looking forward for the new fans and heatsink to arrive

With current fans on high (but Zalman on low)


With current fans on low (Zalman on low as well) -- mins are about 2C higher.

Just a quick update. I'm up to 4.2GHz @ 1.328V. Bumped a little after the validation ( http://valid.canardpc.com/show_oc.php?id=1415797 ). Temps 40-45C at idle and 90C+ on load... still waiting on delivery of the new cooler to tame that down.

Got the CPU fan further silenced down with a custom profile in the bios. Running at 60 or 70% on top of using the silencing resistor that came with it.

I do not think that I'll be able to overclock this CPU any further unless I put quite a bit more effort into it, but I suppose 4.2 is okay, and with the new cooler I'll probably have some room to make it quieter as well.

I'm told that even if I went to liquid cooling I would probably only get another .1 to .3 GHz out of it, given the voltages involved and the fact that it is a 24x7 OC. So I think that is pretty much where it will stay.

Since windows is now turning off my HDs after 10 mins there are perhaps 3 main types of noise:

1) A very low frequency fan hum, almost vibration like, which I think I have a shot at taking stabs at.

2) A slight higher frequency periodic spinning kinda noise... could be one of the fans going through some cycles of under-voltage (?).

3) Perhaps some coil noise, very faint, and... and

4) All those crickets inside my head

Hope to get the new fans and sink over the next few days and we will see the results. Though the changes may take me a couple of days as I need to do some case mods.

How are you managing to measure the dbA SPL reported in your first post?

I had a BK Precision 732 sound level meter laying around. Measured it at 1M from the case. I measured it in "A" mode and "Slow" at its lowest range "30-80 dB"



Curious... Why do you ask?

I got all my Noctua fans and after some testing I have to say that I'm rather disappointed.

Unfortunately I could not measure air flow. So I was limited to measure RPM's (digital tachometer), voltage, and noise.

Turns out that RPM by RPM they put out about the same noise as the Antec Tricool. Here are some measurements.

Note that all measurements were taken at a distance of 12 inches from the fan, with it blowing air away from the meter.

120mm Tricool - Transparent
High 1830 rpm 45.5 dBA (very loud)
Medium 1455 rpm 39.1 dBA (too loud for me)
Low 925 rpm 31.3 dBA (still audible, but not too bad)

120mm Tricool - Black (the one that comes with the case)
High 2005 rpm 46.8 dBA
Medium 1550 rpm 39.5 dBA
Low 971 rpm 31.2 dBA

120mm Noctua NF-P12
High 1308 rpm 36 dBA
Medium 1030 rpm 31.7 dBA
Low 915 rpm 30.5 dBA (almost silent)

120mm Noctua NF-S12B FLS
High 1215 rpm 36.4 dBA
Medium 955 rpm 31.9 dBA
Low 690 rpm 29.9 dbA (virtually silent)

As you can see the 900-1000 rpm is the boundary where you hit 30-31 dBA at 1 foot -- that is the top of what I'm shooting for -- less is better. I found the noise of the Noctuas more annoying than that of the Tricools.

I did other fans including a couple of 200mm ones. I'll post more tomorrow. Getting too late now.

I'll check again tomorrow for how low I can run the Antecs (resistor or zener) and how much flow they seem to be putting out. But right now it does not look good for the Noctuas.

BTW, I'm not sure at what distance the manufacturer's measure the noise. Gotta be in very different conditions than I did.

Here is a chart of some of the measurements I did yesterday.



I'll mount the fans (single fan on push) on the Megahalems and adjust speed to match 31dBA at 12 inches which seems to be my upper limit for fan noise -- should be around 900-950 rpm depending on the fan. Then report the respective temps on idle and under Prime.

Actually I'll redo the measurements first because I think a few of the data points were captured in "A/fast" as opposed to "A/slow" which bumps dBA's by +1 or so.

Word of caution -- since 30 dba is the low limit of your SLM, you can't really trust measurements that fall very close to it. 29.3 dba is room ambient, you say, but it could be lower. Anything below 30, you just don't know what it is.

Fan makers measure at 1 meter -- a fairly widely accepted standard for SPL measurements.

Yes, but it still strange because my 31 dB (900'ish rpm) at 1 foot is equivalent to 20.7 dB at one meter according to this site http://www.sengpielaudio.com/calculator-distance.htm (1m = 3.28ft)

That is a big difference from the advertised sound levels for these products.

Edit:

Noctua says 10db and 12db at 900 rpm 1m for the P12 and S12B. See http://www.noctua.at/main.php?show=nf_s ... son&lng=en

I measured 30 and 32 at 12 inches which according to the site above translates to 19.7 and 21.7 respectively. Off by almost double. That is a huge discrepancy. Weird. What gives?

Edit 2:

May be they measured at 1 foot and applied the inverse distance rule forgetting dB is a log scale

Extrapolations of SPL measurements taken very close up are not reliable. If we're talking about 1m vs 2m, no problem (in general) but from 1' it's dicey, really depending on room/boundary effects.

Maybe you have not seen these?

http://www.silentpcreview.com/article69 ... tml#noctua

The testing was done before we built the anechoic chamber, and results below 20 dBA are not very reliable... but as you can see for this S12, at 1020rpm, we measured 21-22 dBA/1m.

We haven't tested the more recent Noctuas in a fan roundup, but we have examined them in the context of heatsink reviews:

http://www.silentpcreview.com/article1020-page5.html

Both P14 and P12 were tested here, in the anechoic chamber. the <20 dBA readings are very accurate. At 900rpm we measured 16 dBA/1m for the P12. Way higher than the claimed 10 dBA.

We (SPCR staff) have never liked any of the Noctua fans. They are, imo, way overpriced and not smooth or quiet enough compared to much cheaper sleeve bearing fans... like the Scythes.

Actually I saw a bunch of your articles -- all very helpful -- and the one I finally used for my decision was this one http://www.silentpcreview.com/article63-page2.html -- however it turned out that the Nexus was not available neither at Amz nor at NewEgg. So I went with what seemed to me the second choice... the Noctua. One thing that turned me off from the Scythe is that they have too many models to chose from.

Tonight I did not attempt to measure things over. What I did was to confirm only those findings that would affect my decision of which fan to use for what. Final choices turned out like this.

1) Replacing the Antec 900 top fan with a CoolerMaster MegaFlow 200. With a Zener 3.9V I get it to do 560 RPM 30.9 dBA 8.25V and 0.113A. That is quieter than the Antec at its lowest setting (370 RPM 31.4 dBA) and the same speed as the Antec's middle position (560 RPM 33.4 dBA). A little bit of a mod is needed to make it fit, but it is worth it.

Unfortunately I can not compare the actual air flow. Still the CoolerMaster noise signature is more pleasant.

Oddly enough voltage alone does not determine the RPM. The results are vastly different when using a diode versus a resistor to slow things down.

2) I'm keeping the Antec's front fans, but I'm slowing them down with a hand matched 3.9V Zeners where they go from 1226 RMP 35.2 dBA in their lowest factory setting to 890 RPM 30.5 dBA and 8.70V. That will give me the blue glow, a very light breeze on the HDs and it will probably be very very quiet. A surprise here was that the screen/dust filter that comes in the nine hundred two had no effect in the SPL.

3) I'm keeping the Antec's back fan, but slowing it down with 25 ohms (4 x 100 ohms in parallel). That gives me 800 RPM at 29.9 dBA 9.5V and 0.104A. I may cut the grid out at the back of the case and leave the fan blades exposed in order to facilitate the flow.

4) I'm adding a 80mm fan for the memories. I had it from a previous project. The model is the "Silencer" #802812 from "PC Power and Cooling". Using it with a Zener 5.1V at 1100 RPM 29.7 dBA 7.1V and 0.028A.

5) For the Megahalems I'll start with a factory Tricool in its lowest setting of 925 RPM 31.3 dBA. I'll measure temps and compare it with the Noctuas.

After I get my machine working again I may experiment later with the Nexus, the Scythe, and the Gentle Typhoon. But they seem all hard to find.

Without a anemometer and making a gig for it it is hard to verify Noctua's claims of increased flow or air pressure. They seem rather noisy to me. When comparing RPMs x dBA the Tricools fared much better IMHO.

Strange.

In the end all fans are all 31.3 dBA or quieter at 12 inches. I'm hoping that gives me very low levels at 1m. *crosses fingers*

The case seems to have great air flow, so the question is really how well will the Megahalems work with a 900 RPM fan. Oh and then there are the two fans of the video cards -- they should be okay -- and that of the power supply, which is only 31.4 dBA at 12", but has a nasty click to it.

Hi,

Here is the power supply noise. It is faint, but there is a weird sound mixed in with the hum -- kind of like the fan has a bit of a sore throat . If you can not hear it raise the volume up (I have to raise mine to the max).

Sorry I do not have a real video camera.

Click on the square below to play.



Do you think it is a defect, something that can be fixed, or just the "sound signature" of the power supply?

I'm sorry, but I can't hear nothing more than the subtle woosh (nearly identical to the Seasonic M12D - its elder brother - noise).

The PSU noise (not the woosh) is not very pronounced. But it is there. One thing is that this was recorded with my phone and they probably have circuitry to remove some level of noise and perhaps that is why the noise detail is not as sharp... or may be it is too low to record with it.

Anyway. The case with the 4 modified fans and the PS at 1m now sounds at 30.8 dBA (without the mobo). The noise level before I started to tinker (just with all fans on factory low) was about 35 dBA. Lets see what happens once we add the mobo, cpu and video cards. I'm hoping that there will not be much of an increase.

The biggest noise maker is the top fan -- I'll look into attenuating it more. It is moving a lot more air than it needs.

The 3 other fans (2 in the front one in the back) are pretty much not audible at this point.

The PSU noise bothers me. We will see if it still there after the case is filled up with stuff and everything is running. The problem is that if I contact XFX they will just think I'm too particular.

Oh well tomorrow is the big day when I replace the sink and put it all back together

I do not understand how the top fan can be that much more noisy on the case than it was on the bench.

May be the very tight fitting (no screws are holding it in place, just the fitting pressure) is causing the fan frame to resonate, or it and the case are working together to increase the noise level.

:confused:

I kind of suspended the top fan and that solved the problem. That fan is now rather quiet. With the case open you get 30.3 dBA at 1m. With the case close it goes up to 30.7 dBA. Which is really weird. You can notice it without a meter as well. But the noise signature is much better than before.

I suppose one positive way to look at it is that the is a lot of air flowing. and the noise is of the air moving through the case as opposed to "fan noise". The cables are a mess so may be when things are more tied up this will diminish.

The numbers above are with a towel on top of the poser supply to mask it off. If the towel is off the power supply the noise goes up to 30.8 and it is much more noticeable because it has kind of a raspy signature.

The sound is now low enough, and diverse enough (PS, fans, air through the case) that the measurements don't help much anymore. At least I'm happy that I got the fans very very quiet. Will be mounting the mobo now... I hope all this work is not lost with the fan on the heat sink.

After all changes the machine went form 35.3 dBA to 31.2 dBA at 1m.

With the Megahalems there was no change in the lows, but the highs came down by 12C.

The performance of the Megahalems is being limited by the airflow in the case. With the back fan on high and the case open the temps drop another 3-5C. But then it gets noisier.

There is probably some room for improvement including try to tweak the overclock to use a lower VCore. But we may be hitting that "diminishing returns" phase -- after all an i7 @ 4.2GHz puts out a lot of heat.

A couple of interesting things:

1) The Noctua turned out to be a better performer per dBA than the TriCool.

2) My case is thermally a better performer open than closed (by 2 degrees)

thanks for an xlnt thread, and thanks to mikec for contributing to it.

i have several nf-p12's, they are a nice fan with a killer warranty, but for cpu use the thermalright ty-14 has been the best i've tried... even quieter than the stock mugen2 fan, but i don't have cooling comparison data between any of these... i'm willing to put up with slightly more noise, if there is airflow/pressure to go with it.

the silver arrow would have been a quieter choice than the megalahems + nf-p12, and it would have cooled better, but you are right about the fitment issues... i had to drill a couple of holes on the inside of my p183 side panel, in order to clear the cooling pipe caps, but you can't see it from the outside of the case.