Quiet 92mm case fans: Zalman or Panaflo

[macklin01]

Hello, all!

I'm considering using 1-3 92mm fans to cool a new case (Gmono with window). I'll most likely be modding it to include a 92mm case intake above the CPU / AGP area, as well as a 92mm top blowhole / exhaust.

The main heat generators in the system are a PIV 3.0C overclocked to 3.5 GHz with an SP-94 and 92mm Panaflo M (running 8-12V based on temperature) and a passively cooled (Zalman HS) GF4 Ti4200. I'll also have a 430W Antec TruePower PSU. (Which has dual temp-controlled fans.)

I'd like to run the 92mm fans in the 5V-12V range. I'm considering:

1) the 92mm Zalman ZM-F2 fan that runs from 38-53 CFM and 20-36.1 dBA
2) the 92mm Panaflo L that runs at 42.7 CFM stock, 27 dBA

I'll consider a 120mm Panaflo L for the blowhole, but the intake will have to be 92mm.

Any and all recommendations are appreciated and certainly will be considered.

I'll attach a pic of the general airflow pattern I'm thinking of in the next post. Of course, any comments to optimize the airflow for a good balance of performance and quiet will alos be appreciated! Thank you in advance. -- Paul

[macklin01]

Here's a rough sketch of the airflow layout:



Here are a few notes:

1) Black square outlines are places where fans can be readily inserted. I've tried to note the sizes wherever possible.

a) The two rear 80mm fan exhaust mount points already exist in the case, although I believe I could modify it to use 92mm fans. However, the aesthetics will likely not be great, since the positioning of the current 80mm fans would require that I offset the 92mm holes from the original center. For that reason, I'd prefer to run 2 80mm Panaflo L's at 5V in those exhausts rather than 1 92mm fan with mods.

b) The front 120mm fan mount point already exists, but it won't allow much airflow through the restrictive front cover. (And modding the front acrylic cover is a non-starter for aesthetic reasons.) I'm tempted to omit it, as in my previous experiences for case cooling, the front air intake does not do all that much to improve cooling when compared to a simple open space there.

c) The top blowhole will have to be custom made with a hole saw through steel. A 3.5" (8.9cm) hole would have to do for a 92mm fan, and I'm not sure what size of hole saw I could find for a 120mm fan. Perhaps 4.5" (11.43cm). I've never put a blowhole in a system before, so I'm not entirely sure at the moment how much it would contribute to improved cooling.

d) The side intake will also have to be custom made with a hole saw through acrylic. From the reading I've done, this can be done carefully with a hole saw, especially if done VERY slowly and running the bit in reverse once the pilot hole is done.

2) Blue squares indicate which of those fans mentioned in (1) I hope to use.

3) Red arrows indicate the general flow pattern.

4) I have numerous 80mm Panaflo L1A's available for use in this case and on hand. Another other fans will be additional purchases.

5) The general theme here is to attain the most efficient air cooling possible for the system to allow for reduced CFM, quiet fans.

Thanks again! -- Paul

[Rusty075]

Before cutting up a pretty case, I'd start with using both the stock 80mm exhausts and no intake, and see if you even need anything more. Maybe try a pair of L1A's for exhaust at 6v to start with.

What sorts of temps are you running now?

Another noise-less mod you may want to consider is ducting the SP94 to the side panel, rather than mounting a fan there. That way the CPU will be drawing in the coolest air possible.

[macklin01]

Hello, and thanks for the tips!

Actually, I have the system running in a current cheapo case from years ago at the moment. In this setup, I have two 80mm Panaflo L's: one as a side intake, and the other as an exhaust. When running full load, it seems I need to run them at full speed to get good temps. (high 40's to 50's C, although I trust onboard thermal readings only slightly more than political campaign promises) At idle, temps are alright running them about 7V, but when I forget to switch them to full speed and start running at full load, it takes a very long time for the temps to come back down when I'm done, even if switching to full fan speeds to do so.

Ducting, rather than a side intake, is an interesting idea. I've always found that a side intake at extremely low speeds does a very good job of supplying fresh air to the area with little to no noise penalty, but then again, I've never actually tried extending a duct all the way to the HSF. I'll have to keep that in mind ...

I want to fully plan my case mods before I move over to the new case. This helps to fully minimize the hassle of removing parts, cables, etc. I had hoped to just do this once while the case is clean and easy to work with.

Thanks again! -- Paul

[maxxymus]

Well from what people around here say... the Panaflo 92mm aren't that silent. From my personal experience, the Zalman 92mm EVEN with resistor is not silent at all.

My recommendations:
1. Forget intake. Work on exhaust. Negative pressure will pull air inside.
2. Remove 92mm fan from HSF, and put 80mm L1A instead at a voltage that suits your audiophile needs
3. Remove 120mm intake fan and if temps are high, cut 120mm blowhole at top and put it there running at low voltage (~7v).
4. Like Rusty said, put another 80mm L1A as exhaust on the back running at whatever voltage that suits your needs.

Optional things:
1. Bottom vent with air filter, see Bluefront's amazing album for pictures on these things.
2. Side duct to the CPU HSF. It seems this is a nice way to cool the CPU without resorting to high voltage fans.
3. PSU duct - also search on the forums for pictures of these things. There are many innovative ways of accomplishing this and it seems the results are very good as well.
4. Fan mufflers - can be made cheaply out of cardboard for testing purposes and then make a more permanent one out of aluminium + sound absorbing foam or any other thick dense foam.

Other basic stuff:
1. Vibration dampeners, washers, grommets, etc.
2. Suspending HD's in 5.25" bays.

Yadda yadda yadda..

Good luck.

[pdf27]

If you do want a 92mm fan, Papst ones are pretty good. Mine is quieter @12v than my Zalman 92mm was @7v.

[Ralf Hutter]

I'd vote for the 2 80mm L1A's as exhaust, running at 5-7V. No front intake fan but open up your bezel for better airflow. I think there's some pics of a Gmono modded this way floating around the forums somewhere.

If that's not good enough, kick it up a notch with a side intake duct to the CPU.

I'd stay away from the blowhole completely as it will destroy the natural "lower front to upper rear" airflow through the case.

[macklin01]

Thanks for the tips. I'll have to give those Papst's a look ...

I like the ideas about negative pressure allowing the air to be drawn in.

I am thinking pretty serious about the bottom intake idea with filters. Since I've always stood my PC on a wooden platform, rather than carpet, there's good potential there for some flow. I'm thinking about adding some taller feet to the case and also cutting some material out of the platform to further help.

The side duct (rather than intake fan) sounds like a good idea, too. I'll definitely be looking into that.

As for the 92mm Panaflo M fan on the HSF, I'm afraid that'll probably need to stay. I do some pretty heft computational fluid mechanics / biophyics work with this computer, and so it runs at full load at 3.5 GHz for days at a time. I guess the goal is much closer to "quiet performance", rather than silence, as far as the noise preference spectrum goes ...

I'll definitely be using rubber washers / grommets, etc. to isolate the fans. Always been a good practice. Was also giving some thought to the suspended hard drive, although it's nowhere near the main sound source for me. I was even toying with the idea of making a foam drive enclosure with heatpipes extending out of the package, so it would be sufficient to cool a high-performance drive, rather than a 5400 RPM drive ...

I'm still toying with the idea of the blowhole up top. I've seen mixed reviews on it.

I remember that article on the PSU duct. I thought it was fascinating. I'm not sure how easy that would be with the PSU intake being on the bottom of the PSU, however. I'll definitely give that some thought ... (And thanks for the reminder!)

And I agree with the (one of the) voice(s) of reason above (Rusty075): I'll probably instead take a multi-step approach, assemble with what I have, and determine further need from there ...

Thanks again, all! Thank you for making me feel so welcome here at spcr. I look forward to continued collaboration. -- Paul

*edit*
Ralf! It's great to hear from you! I'll definitely search for that gmono mod. I've thus far also shied away from the blowhole.

What do you think of a bottom intake instead of front intake? -- Paul */edit*

[HokieESM]

hey macklin01 -- i see you're doing CFD. I do a lot of computational solid mechanics (penetration/impact simulations mostly), so I completely understand the "running 24/7 for days at a time". I would recommend you download MBM and watch your temperatures..... some people still see the temperature "rising" (however slight) after 24 hours of computation (the time constant can be large).

As far as your setup--just go with two rear 80mm... possibly on a fanbus. Turn them up according to the case temperature. A Zalman FanMate on the CPU HSF is also nice--you can "dial" it in to the necessary voltage. For just _quiet_ (and quiet by sane standards, not by some here in the forums <grin>), just get some reasonable airflow and you'll do fine. I put together a Prescott 3.0E system for another grad student recently in a Antec 3700BQE, and it was reasonably quiet by general computer standards (but by no means silent). And your Northwood probably puts out less than that Prescott.

If you're just looking for _quiet_ performance in a hard drive, just pick up a Samsung Spinpoint--I don't think there is ANY way you're going to hear that over an Antec True430 (or at least I can't hear my SP1614N over mine)--even not suspended.

I'd avoid the blowhole--simply for the reason that its probably just wasting your time. If you're just looking for quiet performance rather than out-and-out silence (or "very quiet" by the standards here), it can be done with off-the-shelf parts.

Good luck!

[macklin01]

Thanks for the tips. (And interesting computations, btw.)

That's the route I'll likely be going, or similar to it. (In fact, it's similar to my current setup.)

I have a homemade fanbus for the case fans, does 7V-12V. As for the HSF, I use the built-in hardware PWM of my Abit AI7 to control the fan from 8V to 12V according to its measured temp. Same for NB. The hdd is fairly quiet, so I'm not too worried about that.

Never did get quite the answer I was looking for for 92mm Panaflo L vs 92mm Zalman, but it looks like that'll be a nonissue for now.

Just curious -- how loud does that PSU get? If it's too terribly bad, I might consider a PSU duct as was mentioned.

Interesting points about the CPU temps over time. Alas, MBM isn't compatible with Abit's lousy stinking AbitEQ (their version), and it isn't available in linux, which is where I do my computational work. (Intel's compiler produces such better code. )

End of the day, I'll probably try 2 low-voltage 80mm's as exhaust, no blowhole, perhaps a side duct / intake (I noticed a great improvement with that on my current case), and possibly a 120mm bottom intake. My fanbus will be temporarily out of commission (I'm going to redo it a bit, I think), but the CPU and NB fans will still be temp-controlled.

From what I've read, there isn't much of a performance gain to be had to have active NB cooling over passive, so I might just get a passive Zalman cooler for it. I wish there were a passive sink with the "correct" mounts for the Intel chipset ...

Thanks again for the tips. You folks run a nice forums here. -- Paul

[HokieESM]

The Antec True430 isn't horribly loud.... but its definitely above what the people here would call "quiet". Check out the "recommended" PSUs here if you really want something quiet. (if you're just looking for "quiet enough", use an ATX tester and see how loud it is)

As far as the Zalman vs Panaflo, I've only used the 92mm Panaflo L1As. They're relatively quiet down below 9V (but your Abit software doesn't go much lower than that).

As far as the Linux compiler--I know what you mean. I dual-boot W2K and Fedora Core 1 to runs Intel Fortran Compiler in Linux (I saw a FORTY percent improvement in computational time over g77 in windows). But you can always use a crappy compiler in Windows to stress the CPU for a few days and watch the temperature. Mine peaked after 27 hours... and just hovered.

Yeah, and put a Zalman passive NB cooler on there, if you can. Those little whiney 40mm fans suck. (and you can get away with it... Intel's 875 board just has a big passive heatsink... and Intel is a bit conservative with everything).

Anyways.... good luck. Scientific computation is not something a lot of the computer sites out there don't consider. Look at SPECfp results.... they can really contradict the gaming results (seeing a Prescott handily destroy a Athlon64FX in floating point calculations, for example.... something gaming benchmarks refute). BTW, if you ever want to judge your system's performance at CFD... make sure to check out the SPECfp benchmarks--part of the "suite" is a CFD code (and they give individual results, so you're benchmarking with something close to what you're doing).

[Ralf Hutter]

*edit*
Ralf! It's great to hear from you! I'll definitely search for that gmono mod. I've thus far also shied away from the blowhole.

What do you think of a bottom intake instead of front intake? -- Paul */edit*

Bottom intake sounds like a good idea, as long as your HDDs are getting some cooling arflow in the bargain.

BTW - Go with the Panaflo over the Zalman. The Panaflo isn't the greatest, but it's waaay better than the noisy Zalman 92mm.

[hero]

BTW - Go with the Panaflo over the Zalman. The Panaflo isn't the greatest, but it's waaay better than the noisy Zalman 92mm.

Ditto. The Zalman is loud.

[dasman]

I have a similar box that runs F@H 24/7 -- P4 3.06 w/ SP94 and passively cooled Radeon 8500.

I run a Papst 8412N/2GL@12v (80mm) on the SP94 (1300rpm, pretty quiet) and a Papst 4412F/2GL@9v (120mm) as exhaust. Temps are 53 CPU, 30 Case and 28 harddrive (spinpoint). Ambient is 75f. Case is a 3700BQE.

I had a TP430 PSU and ditched it for a modded Seasonic -- much quieter. Ended up putting a PSU duct on it (here).

I may do a bottom intake/HD duct if things get too hot over the summer, but right now I'm kinda thinking it won't be necessary -- the only thing I think I'm going to have to do is go with a higher flow CPU fan during the summer, the Papst is pretty low flow.

As for 92mm fans, I've had good luck with 92mm Acoustifan's (but bad luck with the 120mm version). If you use the thermally controlled version as the exhaust, you won't have to worry about your fanbus...

Dave

[macklin01]

Thanks again for the tips, everyone!

I'm thinking very strongly of a 120mm Panaflo L bottom / floor intake running at low voltage.

If necessary, I'll try a 92mm side duct to the CPU, and after that and if necessary, I'll finish drilling the holes in the side and throw on a quiet 92mm panaflo at low voltage.

All the rubber grommets, etc., will be done as is typical. (Well, I need to order some more from McMaster, but you know ... ) Also, I'm almost done "sleeving" the PSU cables with a small-diameter spiral wrap. Should be very sharp for cable management.

Had a real analysis midterm this morning, so I think I'm going to get started on those lousy fan grills with my Dremel this afternoon to reward myself for studying. (And to get back at my neighbors for being noisy at 3 AM on a Sunday night / Monday morning. <insert evil grin here> )

As for the PSU duct, first off, fantastic work, dasman. Mine will need to be a bit more complex, as the PSU has a bottom fan, but I have an idea up my sleeve that I'll post later if it pans out...

Thanks again for all the tips! Oh, and Ralf, you'll be getting a response to your earlier email sometime soon, when I finish deciding on a layout.

Later! -- Paul

[dasman]

As for the PSU duct, first off, fantastic work, dasman. Mine will need to be a bit more complex, as the PSU has a bottom fan, but I have an idea up my sleeve that I'll post later if it pans out...

Thanks

If your budget allows, ditch the PSU -- you won't be sorry...

Dave


PS You might be better off running the fan as exhaust, rather than intake

[macklin01]

As for the PSU duct, first off, fantastic work, dasman. Mine will need to be a bit more complex, as the PSU has a bottom fan, but I have an idea up my sleeve that I'll post later if it pans out...

Thanks

If your budget allows, ditch the PSU -- you won't be sorry...

Dave


PS You might be better off running the fan as exhaust, rather than intake

LOL, can't do that. As I just bought the PSU for the computer so that I can ensure stability under long-term loads with 4 sticks of RAM, I think I would be sorry!

BTW, which fan did you mean to run as an exhaust? The bottom fan?

Thanks -- Paul

[dasman]

LOL, can't do that. As I just bought the PSU for the computer so that I can ensure stability under long-term loads with 4 sticks of RAM, I think I would be sorry!

You sound alot like me when I bought my TP430 . Then found I was only drawing 220W at the wall which translates to ~150W draw in the box (assuming 65-70% efficiency). This with 1GB Rdram (4 sticks), (4) raided Seagate 7200.7's, a couple of fans, etc, etc.

You'd be surprised what you can run on 300W with a quality PSU (Antec is good, just a little noisy).

BTW, which fan did you mean to run as an exhaust? The bottom fan?

I meant to ditch the intake fan completely and put it as an exhaust out the back. Putting the fan as exhaust pulls hot air out of the system and helps the general airflow through the box. Putting it as an intake doesn't increase your airflow, but will provide spot cooling (like for a HD), if you need it.

Example: Lets say your TP430 pulls 25CFM (I don't know and couldn't find the number on Antec's site) and the Panaflo L does 68.9cfm @12v. Putting the L on intake puts 68.9cfm of fresh air into your box -- the PSU sends some of that out the back and the rest goes out through the back fan hole (which is unused?).

Now, put the Pan L as exhaust -- you exhaust 68.9+the 25CFM from the PSU -- that's 93.9cfm of fresh air that needs to be drawn out the box. As long as you close off all of the leaks and your bottom intake is big enough (so you're not starving for air), all 93.9cfm will enter through the bottom intake, whether it has a fan or not.


Dave


PS I'm working on another box for a file server in my basement -- very dusty and all of the HD's are mounted in 5.25 bays. I'm sealing up the case and putting a filter in each side panel -- right next to the drives. Then I'm filling every fan mount in the box with a fan blowing out -- all of the air will come in the side doors, across the HD's and then out the various fan mounts. Since it's in the basement, I don't care about noise but I do care about keeping the dust out and the HD's cool. Adding intake fans would be redundant -- I'll have (5) 24cfm fans blowing out so I'll have 120cfm blowing across the HD's. If I added 5 intake fans, I'd still only have 120cfm blowing through the box -- only a 6th would change things...