Fan positions

Control: management of fans, temp/rpm monitoring via soft/hardware

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Dizzie
Posts: 15
Joined: Sun Aug 11, 2002 3:26 pm

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

So the intake fans supply the cold air and the extraction fans take the warm air away right? So which are more important. Surely if you've got loads of intakes then the air will find a way out somehow and if you have loads of extraction fans then air will find a way in.
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<BR>Which are more important?
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<BR>Currently I have a lian li pc12 case. 2 standard intakes on the front and 1 extraction fan on the rear as shipped. No matter what I do the case temp reaches 30oC and the CPU 40oC Idle. When I had a smaller case I could get the case temp down to 23oC ish.
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<BR>Any ideas?
[addsig]

Archant
Posts: 3
Joined: Sun Aug 11, 2002 3:26 pm

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

My case has two fans, one in the psu and one on the cpu. My entire case does however get hot after a while. It's a miditower with a Barracuda, Athlon, Matrox and the usual stuff. The cpu reaches 50 C, system temp is 40 C, the hd is a little cooler than the rest and the gpu is hotter than the cpu. My conclusion is that the psu fan is not enough, especially since I have modded the psu (an old Q technology) with a 12 db 80 mm Papst.
<br>I tried to lower the temp by adding an intake fan. It didn't help however, enough air was apparantly sucked in throught the front anyway. My front intake holes are very small, but I can feel the air flowing (slowly) if I put my hand there.
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<br>I want to add exhaust fans but my case doesn't support any =(
<br>If I have the time, I will drill a hole in the back of my case and add another Papst.
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<br>In my (short) experience, intake fans are overrated. If I had many (or strong) exhaust fans, I know I would need an intake fan to supply the exhaust fans with enough air. But right now an intake doesn't help.
<br>Perhaps I will benefit from my intake fan if I drill that hole and add a Papst exhaust fan. But I'm not sure, because in that case, I will turn down that fan and my psu fan to 7 V. =)And two fans at 7 V are not much better than one at 12 V.
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<br>The ultimate solution I think would be 4 (or as many that fits on a miditower) 80 mm exhaust fans - all Papst at 5 V. =) And 1, perhaps 2, identical intake fans.
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<br>Comments?
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hutts
Posts: 17
Joined: Sun Aug 11, 2002 3:26 pm
Location: Brisbane, Australia

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

I've been messing around with fans a lot just lately in my quest to silence my computer. Well it's not silent but it's very quiet all the same. I just need to add a Baracuda 4 sometime and it'll be to my liking. My aim has been to maintain normal level of cooling and reduce noise.
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<br>So, I've doubled the fans , set them at 5 volts and done a few mods with the video card and cpu. My system has an Athlon 750 with a Geforce2 GTS and a Seagate Baracuda 2. I use a Zalman fan bracket to hold 2 90mm fans over the cpu and video card(which I added a new sink to), and I've added two extra fan holes to the case ; one at the front and one at the back under the PSU. The system temp used to be around 31C with the Video Card around 47. Now the system is around 27 and the video card around 42. Hard disk runs at around 39 and I don't know what the cpu is as I don't have the extra sensor for my ASUS board pfft!
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<br>From experience, exhaust fans are more effective. Put in the right place, they remove the air where it needs to be sucked out, and cool air will find a way in. Intake fans will help the air flow a bit removing some resistance and maybe lower the temperatures. In my case the computer case has air holes along the side and some at the back, so I've added the fans at the front to encourage air to enter at the front rather than towards the back of the case.
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<br>There is a fair bit to be said for balanced airflow, but my opinion is that if you can't balance it, have the greater flow for exahust.
[addsig]

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