Changing Exhaust Fan on el-cheapo power supplies

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

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tomk
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Post by tomk » Mon Aug 12, 2002 2:32 pm

I just bought a new computer and the power supply sounds like a jet engine. I've read your mod on changing the exhaust on an enermax ps (which is really cool).
<BR>
<BR>Do you all think that same thing would work on my stock PS? Or is the heatsink/design of mine (I'm sure it's not thermister equipped) not useable with one of those quiet low-flow fans?
<BR>
<BR>This is a great site, good work.
<BR>
<BR>-tomk
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MikeC
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Post by MikeC » Mon Aug 12, 2002 2:32 pm

Do you all think that same thing would work on my stock PS? Or is the heatsink/design of mine (I'm sure it's not thermister equipped) not useable with one of those quiet low-flow fans?

This is a great site, good work.
tomk,

Thanks for the kudos. :)

The Panaflo @ 12V has cooled any & all PSUs I've tried w/o problems. It has also worked fine at 5V, but PSU temps do go up a bit ~8C (typically under 30C @12V) -- see this page in the article about running a PSU w/o a fan. This is perfectly safe when ambient temps are reasonable -- say below 30C? -- and the case is reasonably well ventilated.

You can tell if it is thermistor equipped by looking for any labels that say "thermal control" or "noise control"on the outside of the PSU. They usually like to advertise the fact.

Tell us full details of the PSU -- and the system -- if you need/want more specific advice.
Last edited by MikeC on Sat Sep 28, 2002 8:43 pm, edited 2 times in total.

tomk
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Post by tomk » Mon Aug 12, 2002 2:32 pm

I'm running a P4 1.8 in an industry rack box with a large intake fan in front,
<br>and the PS in the back. 2 WD 40gb 7200 HDs, (not as loud as I'd expected)
<br>and a geforce 3 TI videocard, (also the fan doesn't make much noise)
<br>
<br>The PS is a Turbo Links Switching Power Supply CWT-420ATX-12v.
<br>It has 2 fans, and sounds just like a hair dryer. It is far louder
<br>than any other item in the fase.
<br>
<br>I'm thinkin it might be worth the experiment of removing one fan,
<br>and then switching the other fan out for a panaflow. I figure if I'm gonna
<br>invest in a enermax it would make sense to first mess around with the
<br>PS that I already have. Also, it may be worth it to swap out the front casefan
<br>for a panaflo fan.
<br>
<br>Finally, I added carpet padding to the walls of my last ATX full size case,
<br>and it did do a bit of muffling, so I was thinkin of doing the same to this one.
<br>
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MikeC
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Post by MikeC » Mon Aug 12, 2002 2:32 pm

Yup, I agree -- mess with this one & see if you can quiet it first. Taking out a fan will help, but you'll also want to slow the other one down. In fact, just try slowing all the fans down first. 7V or 5V -- if you don't know how, check in the <!-- BBCode Start --><A HREF="http://www.silentpcreview.com/modules.p ... d=6&page=1" TARGET="_blank">12/5V switch</A><!-- BBCode End --> switch article.
<br>
<br>I presume the fan setup in this PSU is the same as in the Enermax?
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tomk
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Post by tomk » Mon Aug 12, 2002 2:32 pm

Ok, I slowed both the rear PS fan, and the front large casefan to 5v.
<br>Then I made one of your switches so I can run then at 12v when needed.
<br>Finally, I removed the second fan from the PS.
<br>
<br>It is WAY more quiet, not nearly silent, but more like a regular computer
<br>than a rack mount hair dryer.
<br>
<br>Now I need to do some scientifical testing of things. How do I know
<br>what the operating temp of my MB and CPU should be? Right now after
<br>running in BIOS setup, I'm watching the temp creep up.
<br>
<br>The MB started at 20C and after 30mins it has reached 27C
<br>The CPU started at 40C and is now 43C
<br>
<br>I felt behind the PSU and not much air is coming out, but the air that
<br>is feels a bit warm... uh oh..
<br>
<br>What do you think?
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MikeC
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Post by MikeC » Mon Aug 12, 2002 2:32 pm

My P4-1.6A oc'd to 2.25G idles ~42-3C. Mobo temp is 25C. Intel doesn't seem to specify a max core temp for the P4 but says it will shut down at 135C. <IMG SRC="modules/phpBB_14/images/smiles/icon_eek.gif"> The CPU case temp shoudn't go higher than mid 70s. I think you're safe. The mobo temp is ok all the way to around 40C, in my experience.
<br>
<br>BTW, if there are vent holes on the side opposite the main fan, and the 2nd fan is over the CPU like in the Enermax, then blocking all other inside vent holes will probably improve cooling for both the PSU and the CPU by creating a more efficient airflow path. You could try with duct tape & see what happens before & after.
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tomk
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Post by tomk » Mon Aug 12, 2002 2:32 pm

I was wondering about that. Thing is, it is a rack-mount case, so it sits horizontally. Thus, even tho the PS fan sucks from what would be "over" the CPU in a normal box, it sucks sidewise in mine. So I guess I get no convection action.
<br>
<br>I'm thinkin I'll be getting a few panaflows and switch them out with the current fans, it's so cheap, I may as well try. I also think I'll do that CPU heatsink fan conversion- but I was wondering, did you hook your panaflow up to the same CPU fan jack on the motherboard? Because the intel fan has a speed control, and BIOS monitors the CPU fan speed. Did you forgo that?
<br>
<br>-tomk
<br>
<br>p.s. thanks for all your help. this is exactly why I love the internet.
<br>
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MikeC
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Post by MikeC » Mon Aug 12, 2002 2:32 pm

It's not only about convection. Closing up the other vents will narrow the airflow path and should concentrate & accelerate the airflow over the CPU area, maybe the PSU HS too. Why not try it & see what happens to CPU temps? And tell us, it'd be interesting to test the theory. <IMG SRC="modules/phpBB_14/images/smiles/icon_smile.gif">
<br>
<br>I did forgo the rpm monitoring. I set mbm5's CPU alarm feature to go off at 65C in case I don't notice when the fan stops.
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tomk
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Post by tomk » Mon Aug 12, 2002 2:32 pm

I haven't gotten around to testing the PS with duct tape on the back vent holes, but I did do a bit more testing of overal temps, and even made a graph in excel. The end result was that after an hour, it's leveled off at 33c and 46c while running bios. This is compared to the same machine w/o any modifications which runs at 27c and 42c. (It's nice to have a control group)
<br>
<br>I also have re-confirmed that when operating in 5v mode, the only thing I can really hear is the CPU fan...
<br>
<br>Now I'm waiting for my panaflos to swap out of the PS, and to do your same CPU HS mod. Fun fun fun!
<br>
<br>-tk
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tomk
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Post by tomk » Mon Aug 12, 2002 2:32 pm

I have 2 questions for ya'll:
<br>I just recieved my panoflo fans, and am about to start swapping them for my noisey fans. I notice that the panaflows have 3 pins coming out of them, but only 2 wires (+ and - ) the third pin is labled "s" does that mean speed?
<br>
<br>Does this mean I can connect that up for the HSF mod and then get the speed (or control the speed) of the panaflo HSF replacement?
<br>
<br>Next part, who knows where to get those little 2 and 3 pin connectors, as well as those IDE power connectors? I ended up just soldering to the wires coming out of the fans, but I'd rather be able to swap things around.
<br>
<br>Oh, shit, one more- will the panaflows work at 5v, or should I make a 7v/12v switch instead? I thought I remember reading that you had trouble getting them to work at 5v.
<br>
<br>thanks a lot.
<br>
<br>I'm obsessing.
<br>
<br>it's fun.
<br>
<br>-tomk
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tadas
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Post by tadas » Mon Aug 12, 2002 2:32 pm

I had some exp with one el cheapo PSU several months ago. I changed fan to Papst but then I pluged it I found another problem - high pitched very irritating buzzzzzz <IMG SRC="modules/phpBB_14/images/smiles/icon_evil.gif"> . Now this PSU rests in peace somewhere in thrash <IMG SRC="modules/phpBB_14/images/smiles/icon_smile.gif"> . Check PSU for a minute without a fan
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Gxcad
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Post by Gxcad » Mon Aug 12, 2002 2:32 pm

In my testing every single panaflo I have used (either the 120mm L1A or the 80mm L1A) ALWAYS consistently starts at 5v. I don't know about less than 5v, but 5v and above I'm going to say it will start consistently.
<br>
<br>I've also used one 80mm powercooler fan at 5v and it starts consistently as well. I get the impression almost any fan will start at 5v, so maybe if it doesn't have a try on a better quality psu and see if that helps? Just a thought...
<br>
<br>-Ken
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Edwood
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Post by Edwood » Wed Aug 28, 2002 5:26 pm

DId that to an el cheapo CompUSA 300watt PSU, but it ended up making sparks fly out the back two months later and fried my mobo, CPU, and RAM.

So, just be aware.

-Ed

deeseeel
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Post by deeseeel » Thu Aug 29, 2002 9:38 am

I think the Panaflo fans have a stop sensor.

If the fan stops moving then signal on the "S" connection changes. (Don't know what it actually looks like; haven't tested it with a volt meter or anything.)

MikeC
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Post by MikeC » Thu Aug 29, 2002 9:45 am

AFAIK, the 3-pin connector is on all the Panaflos but if it doesn't come with 3-wires, the circuitry for rpm sensing is not inplace, so that third wire won't do anything.

Oz
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Post by Oz » Sat Aug 31, 2002 8:45 am

I'm getting a couple of panaflos, tailed with 3-pin connectors. Is it better to just use these and plug them into the mobo, or to use a 3-pin to 4-pin molex converter?

Oz
:D

MikeC
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Post by MikeC » Sat Aug 31, 2002 8:59 am

Doesn't make much difference unless you want to run them at 5 or 7V, in which case you have to do the 4-pin -- unless you get something like the Zalman fanmate, which is very cool, BTW.

quokked
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Post by quokked » Sun Sep 15, 2002 6:44 pm

Doesn't make much difference unless you want to run them at 5 or 7V, in which case you have to do the 4-pin -- unless you get something like the Zalman fanmate, which is very cool, BTW.
ba da da dum ting! pun intended?

hyum
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Post by hyum » Sun Sep 15, 2002 11:11 pm

panaflos need a -S suffix, i think, to have RPM sensing. these are optional part (read non-standard) so is usually very hard to find 80mm-120mm panaflos with RPM sensing in retail channels. i think jim at coolcases.com may actually have some, but i'm not completely sure so check at the site or call them.

morganw
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Panaflo w/ 1BX suffix has tachometer

Post by morganw » Wed Oct 09, 2002 4:10 pm

http://www.panasonic.com/industrial/app ... common.pdf explains the part number system.

FBA08A12L1BX would be a 12 volt 80x80x25.5 mm low speed fan with a 3 wire tail and a speed sensor.

Digikey lists them in their catalog but lists all but one model as zero on hand. Their prices are good, so it's worth asking them if they can actually lay hands on the beasts.

I'm looking at Sunon fans as reasonably quiet but easier to get with tachs. I want to run at low speeds, but be sure my fans are actually turning without crawling around on the floor.

I also want to compare fan families to see what's easiest to mod to preserve tach output while PWM speed controlled. If I can get the pullup (from 12V power-in to tach-out) out and pull up with a non-chopped voltage source, I should be able to get efficient speed control (vs. a linear regulator) and monitoring.

-M

hyum
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Post by hyum » Thu Oct 10, 2002 6:46 pm

not an endorsement, but coolcases has the 92mm FBA with RPM sensing for $12.
http://coolcases.com/cart/fans.html

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