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I reduced the noise on my PSU Fan but...

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July 20, 2003 10:32:05 PM

I opened the PSU, detached the Fan, cut the wire, soldered a 66Ohm/0.25W resistance in series with the Fan and put the fan back in the PSU. This has <b>reduced</b> the <font color=blue>noise drastically</font color=blue> and the <font color=red>air flow pretty much.</font color=red>

I also plan to put resistors in series on my 2 Case Fans, but <font color=red><b>i am not sure if it is safe to run it this way.</b></font color=red>

Any suggestions?

<b>i wish i had a <font color=red>million</font color=red> <font color=green>$$$</font color=green>...</b>

More about : reduced noise psu fan

July 21, 2003 5:11:06 PM

Well ofcourse... as long as the temps don't get insane high due to the lower aiflow.
I use the same methode on all my 6 casefans... but you might need stronger/weaker resistors to slow down the casefans to a specific level.

I love my Delta 60HP 7000 RPM fan that puts out more dB then CFM :eek: 
July 21, 2003 6:13:11 PM

tnx for replying svol. The 80mm fans are rated 12V/0.15A. Later tonite i plan to use the 47 Ohm resistance on my 120mm fan and see how silent it runs. What mod have u done to ur case fans? What resistors have u put across them? In series?

The air-flow is not all that bad. May be its half of what it was initially. But i can live with that.

<b>still</b> thinking of a good sig. till then...
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July 22, 2003 4:22:17 AM

Hehe, or just wire the negative lead to the 5v line and get 7v. Without cutting anything or buying parts, or creating waste heat through the resistors.

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>
July 22, 2003 4:26:05 AM

Hehe, or just wire the negative lead to the 5v line and get 7v. Without cutting anything or buying parts, or creating waste heat through the resistors. Sometimes it's just the simple things.

I've grown lazy minded over my ohm's law, you care to give me the calculations and resulting voltage for adding the 47 Ohm resistor?

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>
July 22, 2003 9:20:33 AM

aaah...jeez...wtf....why didnt that occur to me at all!!!

It indeed is as simple as that!!! i wish i cud upgrade my brain cells just as easily i cud upgrade my CPUs. May be that way i cud think better :wink:

<b>still</b> thinking of a good sig. till then...
July 22, 2003 10:13:37 AM

Quote:
or just wire the negative lead to the 5v line and get 7v

i might try doing that. But i want to make sure it wont cause any other problems. right? The last thing i want is a dead comp with nothing to do all day :wink:

<b>still</b> thinking of a good sig. till then...
July 22, 2003 8:58:23 PM

Nope, I've done it myself several times. Fans are plastic, so you don't need to worry about them grounding out the +5v lead. And the voltage difference between +5v and +12v is 7v. Works perfect for making a high speed fan opperate at about 1/2 it's original speed, and around 1/4 the noise!

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>
July 22, 2003 9:06:25 PM

cool. i'll try it myself then. tnx again for the idea.

<b>Take my advice, I don't use it anyway.</b>
July 23, 2003 9:38:36 AM

Hey Crashman, which is the -5V line? which color wire? I have to by pass a connection from the -5V line on the power connector that goes into the mobo?

<b>Take my advice, I don't use it anyway.</b>
July 23, 2003 3:06:25 PM

DON't juse the -5V line, use the red +5V line. The -5V line can't cary a very big load and you don't wont to overvolt your fans (12--5=17V voltage difference).

I love my Delta 60HP 7000 RPM fan that puts out more dB then CFM :eek: 
July 23, 2003 4:46:54 PM

svol is right, use a +5v lead. On your molex connectors, +12v is yellow, +5v is red, so....connect the fan's yellow wire to yellow, and the fan's black wire to...red.

It's really rather simple. Just make sure you're only doing this with the fans.

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>
July 23, 2003 7:38:55 PM

DUH!!! LOL...

What was i thinking!!!

First i was a bad Mathematician. And now this. Its a pity and shame that i am studying to graduate as an Electronics Engineer.

<b>Take my advice, I don't use it anyway.</b>
July 23, 2003 7:59:40 PM

man, i almost started to look for the -5V line on the connector :lol: 

<b>Take my advice, I don't use it anyway.</b><P ID="edit"><FONT SIZE=-1><EM>Edited by TheMask on 07/24/03 02:06 AM.</EM></FONT></P>
July 23, 2003 8:41:47 PM

Although, running the fan at 17V might be useful for overclockers who need more air flow...

Then again, there are always fans from hair driers that'll move as much air ... and sound just as loud. He he he.

<font color=red>Is that an airplane taking off?</font color=red>
<font color=blue>No, it's just my overclocked AXP1700!</font color=blue>

"<i>Yeah, if you treat them like equals, it'll only encourage them to think they <b>ARE</b> your equals.</i>" - Thief from <A HREF="http://www.nuklearpower.com/daily.php?date=030603" target="_new">8-Bit Theater</A>
July 23, 2003 8:49:42 PM

Or may be i'll just keep my case open and put on a big fan right in front of it :lol: 

<b>Take my advice, I don't use it anyway.</b>
July 23, 2003 11:24:35 PM

It's easy, here's how I did it: I pulled the pins out of a 4-pin molex connector on the fan (on the input end). Then I put the fan's black lead in place to match up with the power supply's red lead. This worked fine. But I didn't mess with the other end. Why? I chained other fans to it, so I didn't need to pull any more pins.

This resulted in all the fans in the chain getting 7v, with only the first molex connector changed. But...one day I almost forgot I had it wired that way and nearly plugged the loose end into a drive!

So that's about the only precaution, either modify all the connectors, or make sure you don't use the last one for anything but another fan.

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>
July 24, 2003 9:17:22 AM

Crashman, I have 5 Molex connectors popping out of the PSU (in three sets.) The first set of 2 powers the 2 HDDs (this one also has a Floppy connector which i have not connected). The second set of 2 powers the CD-ROM and CD-RW. The Third set has one Molex connector (which is free and which is what i am planning to connect my fans to) and a Floppy connector which i have connected to the Floppy drive.

Wud it matter if i go ahead as it is or wud it be better (which i feel wud be the best) if i connect the floppy from the First set and leave the third set alone for the fans.

<b>I hate scottchen. :wink:
Scottchen's</b> sig: I could only overclock my Barton 2500+ to 2645mhz. My Radeon 9700pro core/mem speed won't go above 410/720.
July 24, 2003 2:42:54 PM

Quote:
Or may be i'll just keep my case open and put on a big fan right in front of it

Hey now, at one point I had my PC at work running that way for over a year because the darn PoS was so unstable. Actually those little AC 'tubo fans' from K-Mart work great because at low setting they're pretty quiet and the air stream is well shaped so you can aim it right at the PC from a short distance and then your cooling just rocks.

Heat was only one of that system's many problems. I've never seen a worse-built PC in my life.

In the end though I finally just broke down an installed a better fan in the case myself. I mean it was only a couple of bucks, but it's the principle of the thing 'n all... I mean why should I spend my own money on my work PC, right?

But once the bearing started to go on that cheap-arsed AC fan the couple of bucks suddenly seemed like a small price to pay just for a little peace and quiet. Still, you gotta give it credit. For such a cheap fan to have run 24/7 for a little over a year <i>after</i> it'd been used under normal circumstances at home for a couple of years is pretty good.

"<i>Yeah, if you treat them like equals, it'll only encourage them to think they <b>ARE</b> your equals.</i>" - Thief from <A HREF="http://www.nuklearpower.com/daily.php?date=030603" target="_new">8-Bit Theater</A>
July 24, 2003 2:50:08 PM

That reminds me, my Antec Sonata's power supply (a modified Antec True380) came with a power line specifically for fans where the power supply trims the voltage on that power line to run any case fans attached to it at lower RPMs when the power supply's temps are down. It's a pretty neat idea. :) 

But that brings me to another thought. My power supply also had a really funky connector on one line. It was rather flat and kind of wide (for just a power connector) and if I remember correctly, all brown. I'm assuming that's a SATA power connector simply because I've just never seen anything like it before. Not having ANY documentation on my power supply (A silly thing to have a case manual and <i>not</i> include any documentation on the special version of the power supply that only comes with that case, no?) I couldn't just quickly look it up at the time. I'd completely forgotten about it until now. <i>Is</i> that a SATA power cable? And if so, why the heck is it so wide?

"<i>Yeah, if you treat them like equals, it'll only encourage them to think they <b>ARE</b> your equals.</i>" - Thief from <A HREF="http://www.nuklearpower.com/daily.php?date=030603" target="_new">8-Bit Theater</A>
July 24, 2003 3:01:05 PM

Yeah, i think i had read it somewhere. Infact i still remember a link was posted somewhere here that showed a Case with a HUGE fan on its side.

Anyways, the temperature is around 28-29 here. i keep one side of my case open. Keeping my case open did help me when i did not have any case fans at all. Now i have cut open a small portion of the front and a smaller portion of the rear of the case. The front "hole" is as big as a 120mm Fan but i have put a 80mm fan there. The rear "hole" is about the size of a 80mm fan with a 80mm fan there. Front is the intake and the rear is the exhaust. With this setup, regardless of keeping the case open, i get the same temp readings.

<b>I hate scottchen. :wink:
Scottchen's</b> sig: I could only overclock my Barton 2500+ to 2645mhz. My Radeon 9700pro core/mem speed won't go above 410/720.
July 24, 2003 3:05:58 PM

Quote:
why the heck is it so wide?

How wide? As wide as accomodating 6 pins? similar (not exact, but quite similar) to the shape of a Floppy connector? what color wires are there on that connector?

<b>I hate scottchen. :wink:
Scottchen's</b> sig: I could only overclock my Barton 2500+ to 2645mhz. My Radeon 9700pro core/mem speed won't go above 410/720.
July 24, 2003 5:22:10 PM

Indeed there is a good chance it isn't a SATA connector but a 6 pins AUX power connector (1 red, 2 orange and 3 black wires in that order).

I love my Delta 60HP 7000 RPM fan that puts out more dB then CFM :eek: 
July 24, 2003 6:19:44 PM

Ah yes, i was thinking about the Aux power connector. cudnt recall the name then. And i was browsing from a internet cafe, so cudnt accurately describe the colors of the wires. i was sure there were 2 orange though :wink: .

I believe that Aux power connector is useful on P4 boards. right?

<b>I hate scottchen. :wink:
Scottchen's</b> sig: I could only overclock my Barton 2500+ to 2645mhz. My Radeon 9700pro core/mem speed won't go above 410/720.
July 24, 2003 9:03:41 PM

The last time I saw the aux power connector used was for powering the riser card on an NLX case. NLX was a newer replacement for LPX, based on ATX instead of AT.

Of course Dells used an Aux power connector on many boards, but it was wired differently.

As for what wires you want to run the fans off...use whichever you want, fans don't draw a huge amount of power.

Again I meantion the increased efficiency of running 7v using the +5v and +12v lines, because transformers are more efficient at reducing voltage than resistors.

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>
July 24, 2003 9:28:58 PM

Tnx Crashman.

<b>I hate scottchen. :wink:
Scottchen's</b> sig: I could only overclock my Barton 2500+ to 2645mhz. My Radeon 9700pro core/mem speed won't go above 410/720.
July 25, 2003 4:47:58 PM

Well I just went to Antec's site to find out what the heck it was and it's an aux connector. So you folks were right. :)  The funny thing is that Antec shows the connector in white on their website, but it was brown on my power supply. It was shaped a bit differently too, but I think only for looks. The pin layout looked the same.

Anywho, I've never heard of an aux connector before. What is it used for? It sure is funny looking.

"<i>Yeah, if you treat them like equals, it'll only encourage them to think they <b>ARE</b> your equals.</i>" - Thief from <A HREF="http://www.nuklearpower.com/daily.php?date=030603" target="_new">8-Bit Theater</A>
July 25, 2003 8:02:44 PM

Some mobo's or PCI cards needs it... but it is really rarelu used. The 4 pin 12VATX pin however (the square one) is often used in P4 boards.

I love my Delta 60HP 7000 RPM fan that puts out more dB then CFM :eek: 
!