• Welcome to Overclockers Forums! Join us to reply in threads, receive reduced ads, and to customize your site experience!

Do my fans just suck or do I have them set up incorrectly?

Overclockers is supported by our readers. When you click a link to make a purchase, we may earn a commission. Learn More.

Gregory_WE

Member
Joined
Jun 19, 2002
My 6 case fans seem like push barely any air whatsoever. They're all 80mm's, and they came with my Directron (Superflower) SF-201 case. For example, for my exhaust fan ontop, if I put my hand over it, I can barely feel a stream of air coming out.

Only thing in my case that seems to push much air is my PSU, if I put my hand behind it then I can definitely feel the air coming out.

Here's my case fan setup:

2 in front intake
1 side exhaust (I'm not sure if I should switch it to intake or not)
2 in back exhaust
1 on top exhaust

My case/CPU is pretty cool, and I've also just recently organized all the wires and stuff inside so airflow is a lot better. But still, I'm not feeling much air being pushed at all from my case fans. What I'm thinking is that maybe I have them powered wrong. I have them all "daisy-chained" (is that the right word? that's what my dad called it)... all hooked up to the same type of connectors as my CDRW drive and hard drive. I figured out that the "Fan Only" connector from the PSU was supposed to plug into the mobo and gave the PSU fans more power... at first I thought that was supposed to be used by my case fans but I guess not.

So basically is it normal that I don't really feel any air being moved from my case fans? Are they defective, sucky, or just set up wrong? I'd like to buy some new ones if they do suck or are defective anyways cause I actually have to duct tape the one on the side down because the whole mounting assembly is pretty cheap.
 
No, the FAN connector from the PSU doesn't give the motherboard headers more power. It just sends rotation signals to the motherboard for monitoring purposes.

Have you got filters or fan guards on the fans? These can be a bit restrictive and cripple airflow. Or you could've just bought quiet fans with low CFM ratings.
 
Well for the front intake fans there's a filter, and then the rest of the fans have a fan guard on the outside.

hmm well plugging it into the motherboard made my PSU fan a lot louder and powerful... before you could barely hear it and it just pushed a fair amount of air, but now it's pretty loud and moves a lot of air. I take it in and out a lot depending on how loud/cool I want my case, so obviously in my case it does effect the rotational speed of the PSU fans.

For the case fans it seems like maybe they're not operating at high enough speed, cause I definitely can't hear them.

BTW here's my case: http://www.overclockers.com/articles533/

Same one there except it's silver not black.
 
What type of powersuppy are you using? If you've got all 6 fans hooked up to same power lead from the power supply you might be over taxing it. Try unhooking all but 1 fan from the powersupplya dn see if it spins faster than it does with the rest hooked up.
 
Ravsitar said:
What type of powersuppy are you using? If you've got all 6 fans hooked up to same power lead from the power supply you might be over taxing it. Try unhooking all but 1 fan from the powersupplya dn see if it spins faster than it does with the rest hooked up.

I highly doubt that. Most likely is low CFM fans and restrictive factory case grills (the ones that are stamped out).
 
Could be that you need more intake fans. In that list, do you inclde the PSU fan?

Gregory_WE said:
Do my fans just suck or do I have them set up incorrectly?

The more fans suck, the better ;)
 
Ok, PSU - Antec True430W. No problem with it, it's pushing a lot of air for me.

Case fans - these came with the case, and they all say Superflower and Ballbearing on them. On the bottom is says DC 12V, 0.14A. That's all that's on them.
 
Hmm

For the PSU fan, it has temperature sensitive exhaust fan so it's speed is designed to vary, but is the plugging in of the fan sensor DIRECTLY changing it's speed? You may want to email Antec about this as this could be a miswiring of the supply.

12V 0.14A? That's a bit low for fans that are on cases. I assume that they are at least 80mm across, which puts them in the low airflow category. Maybe you just have soft and gentle fans. Big Delta screamers aren't that expensive so if you want more airflow and don't care about your ears you could always get a few of them :D
 
hehe, yeah they're absolutely quiet and they are 80mm... I'm not sure if I'll bother though, cause my CPU temp idle (it's summer time too) is around 28C and full load around 38C, with stock intel HSF. Next time I do some major upgrading I may replace some of the fans.
 
One more thing about the PSU fans... when I unplug it from the monitor, the RPM goes way down... I can't remember what exactly it was at as reported by PC Probe, but it was below the lowest threshold setting so I had to turn the sensor off.
 
Excuse me for having a bit of a giggle
...

The PSU fan has a little magnet and a reed or hall effect switch in that sends out pulses of voltage every time the magnet goes past i.e. every time it completes a revolution. Those pulses are sent to the motherboard via the "Fan_sense" wire which connects to the pin which records the pulses. The reason the RPM goes down when you take the fan speed plug out is because no more pulses are reaching the motherboard and so because most motherboards have a lower limit on the RPM they can sense, it goes below that in the hardware monitor, which gets its reading from the pulses. Just to make sure, does the fan ACTUALLY speed up/slow when you plug the thing in? Can you tell by putting your hand in front/listening to the pitch?

The thermal monitoring circuitry inside your PSU adjusts the fan speed depending on the PSU's temperature, so it could be possible that you had your hand in front of it as the fan speed level kicked in and notched it up.
 
The "Fan Only" power from your PSU is a 7v... So all your fans are effectively running at 7v (instead of the usual 12v). The PSU actually controls the speed of your fans, so on higher load they will speed up.

Antec, as shown in this Manual also reccomends that you should not connect more than 3 fans to the single "Fan Only" connector.


rtfm-dude.gif

Case Closed!
 
Last edited:
^ Erm no it isn't. Unless my eyes decieve me it says "Fan only" and under that says

+12VDC
COM
NC
NC

But the superintelligent power supply varies the voltage accordin to the temperature, so the fans would run slower. If you need more speed just hook them up to regular connectors.
 
Sometimes the fans that come standard with cases are not the best. They can be loud, not very effective, or both. If you feel that you need stronger fans, then just switch them out.

I find that removing the stamped grills helps the airflow a lot. It may also make the computer a little quieter. However, if you're getting good system and CPU temps, then I don't know what you're worrying about.
 
I think what the case here is is that these fans are intended to be quiet rather than powerful...

And yes, when I unplug it from the motherboard it moves NOTICEABLY less air (obvious by feeling with hand), and is also A LOT quieter. There is absolutely no doubt in my mind that the speed of the PSU fans is altered by whether or not it's plugged into the motherboard. I plug it in, my case is pretty loud (since nothing else in my case makes any noise whatsoever) and you can feel lots of air coming out. Unplug it, and my case is virtually silent and only a little bit of air is coming out.

Yes that's true I have nothing to worry about with my temperatures, I just like to have everything running the best it can, and I want to make sure nothing's not working like it's supposed to. I guess I'm a perfectionist or something :rolleyes:

Basically here's my setup: I have the 2 rear exhaust fans on the "fan only" connector, then the 2 front intake fans on one regular power connector, and the 1 side and 1 top exhaust fans on another regular power connector. Basically it's pretty much balanced out.
 
Last edited:
L337 M33P said:
^ Erm no it isn't. Unless my eyes decieve me it says "Fan only" and under that says

+12VDC
COM
NC
NC

But the superintelligent power supply varies the voltage accordin to the temperature, so the fans would run slower. If you need more speed just hook them up to regular connectors.

Running at full speed, the PS can put out 12v of power to the fan only connector. At lower temps, it lowers the voltage to 7v.
 
Make the side an intake and it will help your CPU temps as the HSF won't be fighting for the same air, it will be bringing outside air in. I would also cut out the stamped grills all the way to 80mm for the best flow.
 
Back