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Optimum Fan Orientation?

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Optimum Fan Orientation?

Postby Hiatt » Fri Sep 22, 2017 1:25 pm

Hi all,

I've just put together a new PC and had problems with freezes and recognising hard disks. I suspect that this is because I have a passively cooled graphics card which chucks out a lot of heat, and I also have a TV tuner card that chucks out even more. These are all centred around the same area as the southbridge, so there's a little pocket of hot air formed.

There's a grille on the side of the case at that point, so I've mounted a fan there. I have a front mounted 120mm fan sucking air in and a rear mounted 120mm fan sucking air out.

My question is, what do you think is the correct orientation for this side-mounted fan? At the moment, I've got it blowing air out, in order to a) suck the hot air out and hopefully b) suck some of the cold air from the front over it.

Do you think it would be better to suck cold air in and hope it's pulled around the cards by the rear exhaust fan?

All opinions gratefully received!

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Optimum Fan Orientation?

Postby bardrick » Fri Sep 22, 2017 6:09 pm

Download and run Memtest86+, to test your RAM configuration. You might have a bad RAM module. http://www.memtest.org/

Check your Device Manager (System Properties control panel -->Hardware tab -->Device Manager), and make sure you don't have any conflicts. Fix any problems you find, all of them. (A conflict often indicates that you have some drivers that still aren't configured properly.)

(It's possible the problem is heat, but you need to rule out the more basic things first.)
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Optimum Fan Orientation?

Postby Nataniel » Tue Sep 26, 2017 7:23 am

By having the fan pulling air in it is actually forcing cooler air towards the motherboard and CPU which would actually enhance the function of the front and rear case fans.
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Optimum Fan Orientation?

Postby Camdene » Tue Sep 26, 2017 3:49 pm

Id reverse the side fan...have it blow directly in (down) on the South bridge, video card/tv tuner. You may be sucking the hot air away...but...your also sucking the fresh air that's coming in the front and out the back! At least you'll have air circulating around the hot spot!
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Optimum Fan Orientation?

Postby filmore » Tue Sep 26, 2017 7:50 pm

im very doubtful thats a heat issue
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Optimum Fan Orientation?

Postby Trev » Sun Oct 01, 2017 4:47 pm

Unless you have severely overclocked your computer, it should never be a problem. I mean, if a card overheats in regular situations, what will it do when pushed to it's limits? I would begin by making sure you don't have a lemon card. When a PC has difficulties recognizing hard disks, there might be something else.

But enough about what I think, The side fan is usually used to suck air out from that "pocket" of hot air created by the GPU and CPU. As you can see, most regular coolers are pushing the air the that spot. Of course, to send that air out, you need to make sure that there is some air entering from somewhere too. Your PSU is also shooting air out if all of your fans are sucking out air, then you must have a hole somewhere for air to enter right? If not, one of your fan might be competing with another. This might with time, reduce the fan's efficiency or even damage a motor if the case is "air tight" (sort of). You should experiment with both configurations but in my opinion, there is something else that causes all your problems.


Actually, do a Google search with "computer case air flow" and you will see that many people and cases have different point of views...the important things is to get the hot air hot...sucking it hot is one way, the other is to push "cold" air in to force the hot one out. As a general rule of course, hot air goes up...so upper holes are outputs and lower holes are inputs. But as far as I can see, people experience different results with different cases and configs.

Hope this helps!
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