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Jen
15-07-2005, 09:02 PM
Hi all :)

I'm on a mission to quieten down my PC a tad. I have already replaced my iCute 320W PSU which has made a huge improvement, so decided the front case 120 mm fan was next on my hit list. I've just installed a Vantec Stealth (120mm) (http://www.vantecusa.com/p_sf_6025l.html) and hooked it up to a spare 12V molex. To my horror, it is louder than the bog standard iCute fan :eek:

At 12V it pushes through 53 CFM at 1500 RPM, and I am now consider getting a variable voltage controller so that I can run it at 7V instead to quieten it down more. I will crank it back up to 12V if the case gets too warm.

I am thinking of a product sort of like this (http://www.ascent.co.nz/mn-product-spec.asp?pid=109887). I noticed the comment that you cannot use it on a fan that has a start up voltage of more than 5V's. Would my case fan have that? Does anyone has any other recommendations on what I could use? It has crossed my mind to get a fan/temp controller unit that fits in a spare 5.25" bay, but I've heard some of them can be a bit abrupt on the on/off threshold.

Advice most appreciated. :)



<still can't believe my new flash and more $ fan is louder than the iCute one :rolleyes: >

pctek
16-07-2005, 03:50 PM
Hi all :)

I'm on a mission to quieten down my PC a tad. I've just installed a Vantec Stealth (120mm) (http://www.vantecusa.com/p_sf_6025l.html) and hooked it up to a spare 12V molex. To my horror, it is louder than the bog standard iCute fan :eek:

I am thinking of a product sort of like this (http://www.ascent.co.nz/mn-product-spec.asp?pid=109887). I noticed the comment that you cannot use it on a fan that has a start up voltage of more than 5V's.
Advice most appreciated. :)

Well see its says 28dba? Never get anything that says more than 21.
And no it won't work. I tried it with my TT 120mm blue LED. So I had to either chnage it to some other fan or live with it. As its pretty, I live with it. And my friend when he comes over, makes smart remarks about vacuum cleaners...

Murray P
16-07-2005, 03:58 PM
A good resource is Silent PC Review (http://www.silentpcreview.com/index.php) and links therefrom.

I have only used the Zalman fan mates with Zalman 90mm fans, but with no start up problems. GL, Goddie or Billy T should be able to advise on the start up voltage thingy. However, I have run 80 & 90mm fans at 5 & 7.5 volts, hard wired by swapping the wires around, with no problems at all. I suggest you try wiring it up as I did: red fan wire to yellow molex wire, black fan wire to red molex, if memory serves me, that should give 7.5V, but I'll check that out for you. Ignore any yellow fan wires, if there is one, they're used for monitoring when attached to board headers (molex uses yellow for 5V, red for 12V, black is neutral).

tweak'e
16-07-2005, 04:17 PM
firstly forget doing anything with front fans. its best to start with the rear fans first. you have 2x80mm case fan locations at the back of the case. fill these with fans first. what speed or noise is up to you BUT you really need to fill BOTH locations. filling just one means the other location turns into an air inlet making a "short circuit". ie exhaust air gets sucked in, then blowen back out, then sucked back in.. in effect it makes the case fan almost useless.

front case fans always tend to be louder than rear ones which is partly why its best to start with rear ones.

for vairble speed either use varible speed fans (which i think you already have) or a PWM controller. these don't have the problems that other controller has, unfortunatly they cost more. have a look at these (http://www.overclockers.co.nz/product/casemod/controller/tt.shtml) or these (http://www.overclockers.co.nz/product/casemod/controller/ocnz.shtml).

the next thing you can do is cut out the fan grills. this makes them flow so much more air and even tends to make it quieter. use wire fingers guards to replace the grills.

if you do all that, one small catch is some cases don't flow enough air through the front fan locations and plastic case front. you may need to cut out the grills of those and trim the plastic air vents a bit. if you have 3x80mm fans you need the equaivalent of 3x80mm air vents in the front.

Murray P
16-07-2005, 04:19 PM
Edit: Found this among my links. Modifying Fan Voltages (http://www.theddrzone.com/review.php?category=114&id=107&PHPSESSID=3f24e7e2c775ea29a4d662e85bac0ce4). There's even pictures for you on the 2nd page :p

For a quick and dirty method, for testing purposes, use a Molex pass through or Y adapter, cut the wires and rejoin in the config of your choice, use small electrical cable connectors (plastic with brass screws) with the fan wires stuffed in beside the Molex wires.

memphis
16-07-2005, 07:16 PM
I also have the Vantec Stealth 120mm fan at the front of the case,(air in) and another one at the back of the case (air out).

I have them hooked up to a fan controller and turned down low.

The fan controller is in my spare 3.5'' slot (under my floopy drive) so I can use the one spare 5.25'' slot for something else later.

It has made a difference and is worth it but once done I start to wonder about all the fans making noise(graphics card,cpu,northbridge,psu,dps=(gigabyte),case fans and the harddrives make noise as well.

Can put harddrives in hd enclosers,and all the other components can be passively cooled (heatsinks) but you still need air flow coming into and out of the case to bring in cool air and get rid of warm/hot air.

Next thing to do will be putting some sound dampening material in the case to stick it on the inside side covers, bottem inside of the case and top inside of the case.

The antec p180 case sounds like a good case do a google on it. :2cents:

That being said I could allways turn some music on or play games turned up louder so wont hear the noise. ;)

Welcome to trying to make your computer quieter. :D

SurferJoe46
16-07-2005, 07:37 PM
I always try for a slightly positive ( + ) pressure in the case at all times...by that I mean that I push more air in than actually gets out. If you let the case get toward the negative pressure side ( - ) then there's always the possibility that you will slightly starve the PSU for intake air, which it draws from the general case area. Low pressure in the case will cause it to lose airflow thru the power supply, and that's a bad thing. :angry

Next thing I do is make sure that I have a 120mm (4 inch) fan blowing in to the case from the front...to pass air over all my hard drives (8 of then in the tower) and make sure they have the most air they can get in the tunnel that I made for them. Be careful with the ribbon wire..it can surely mess with the airflow! I use 2/80mm fans blowing out in the rear of the case....make sure that all card-slot fillers are in place too! (Those little metal strips that are removed to install a card..they never seem to get replaced when we take them out though.) :p

The only speed controls I am currently using is the one that came on the software for the Enermax PSU that came with the mobo, case, tower kit. I let the programmed sensors take care of the cooling of the CHA and CPU. I use the mobo speaker for any alarms...not the sound card speaker. :thumbs:

Jen
16-07-2005, 07:47 PM
Thanks everyone for your suggestions so far. :)


Well see its says 28dba? Never get anything that says more than 21.Yes, but that is at full tilt. I'm sure when it runs at 7V it will be quieter :p. I also couldn't find any 120mm fans that ran at 21dba, like the smaller fans can.

A good resource is Silent PC Review and links therefrom.

Edit: Found this among my links. Modifying Fan Voltages. There's even pictures for you on the 2nd pageI have been all over Silent PC Review (and similar sites) like a rash lately in my quest for a quieter PC. :D That link you gave for modifying the voltage, was missing all the pictures on the option 2 (Modding a Pass-through) :dogeye: , the first option is not suitable as I don't have A) any welding skills, B) a welder anyway. I am sure I saw somewhere on my travels a little device that was similar where it had an single prong adapter that you plugged into the appropriate molex hole for what voltage you required. Might need to go looking again ...


firstly forget doing anything with front fans. its best to start with the rear fans first. you have 2x80mm case fan locations at the back of the case. fill these with fans first.I think I will do that as well now, even if I leave the front 120mm fan in on lower RPM's just to aid the intake of air.
the next thing you can do is cut out the fan grills. this makes them flow so much more air and even tends to make it quieter. use wire fingers guards to replace the grills.Lacking a few tools for a general hack at my case, so I will try it with the fan grills in place first and then see about cutting out the grill if it is causing a problem.


The fan controller is in my spare 3.5'' slot (under my floopy drive) so I can use the one spare 5.25'' slot for something else later.Is this a fitted 3.5" fan controller? What model is it? I actually have 4x 5.25" bays with 3 currently in use, so there is still room for a 5.25" unit if I decide to go that way instead. You certainly have tackled the noise in your case by the sounds of it :D. But you are right, once you start you want to keep going as you soon find the next device which makes noise can now be heard. I am already thinking of the CPU heatsink/fan and have my eye on a Zalman CNPS7000B-AlCu unit (http://www.zalman.co.kr/eng/product/view.asp?idx=142&code=) (I want to keep the weight factor to motherboard/CPU specifications).

I spotted these (http://www.thermaltake.com/accessories/a2259hardcano13/a2259hardcano13.htm) when I was looking at fan/temp controller units which look really great, but unfortunately they come with a black facing only ...

If nothing else so far, I am really pleased with the noise reduction my new PSU gave and I wish I had dealt with my iCute PSU ages ago. My new PSU is a Enermax Noisetaker 485W with dual fans and fan speed controller. It should last me for a while!

memphis
16-07-2005, 08:42 PM
About the fan controller yes it slots into the 3.5" slot,its a VR Rheobus fan controller with blue led looks good at night not to bright.

I bought it from dragonpc they have different kinds silver and black fan controllers there.

I have nothing to do with them.Its just the shop I buy from here in Chirstchurch.

About the cpu hsf check out the Thermalright XP 120mm or the Thermalright XP 90mm.The XP 90 meets the weight requiremnts for the mb,XP 120 just a bit more heavy but not much.www.thermalright.com to check if it works for your mb.
Thermalright have a good name in cooling like Zalman do as well. :)

SurferJoe46
17-07-2005, 05:38 AM
Just remember that as the volts (to the fans thru the speed controllers) go down, the amps go up...and due to losses in the fan motors, heat will also rise in the fans themselves. I personally prefer to let the fans other than the chipset and processor get full voltage all the time.