Fan Distance from Passive Card ?

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whispercat
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Fan Distance from Passive Card ?

Post by whispercat » Sun Jan 23, 2011 7:41 pm

I'm looking for a new mid tower case for a build that will be based on an uATX board with a quad core 2 duo (65w) and the passive Zotec GT 430 Zone Edition card.

One of the cases I'm looking at is this Lian Li:
Image

There would be one SSD and one HDD (placed behind the lowest front intake fan). The higher front intake fan would basically just blow into the case.

My question breaks down into three parts: 1). How much airflow does this kind of passive card need 2). Would airflow from a 120 mm front intake fan reach the video card and be enough? 3). If it would reach and be enough, how slow can I get away with setting the fan?

Lian Li makes another similar case with just one front intake fan. So perhaps I should also ask, would just one front intake fan blowing over and through the HDD and SSD be enough to also help cool the Zotac passive card?

frenchie
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Re: Fan Distance from Passive Card ?

Post by frenchie » Mon Jan 24, 2011 4:01 am

I would try to place the fan as close to the card as possible so you can run it as slow as possible. I'm not sure it possible to do that with that case though...
Try with only and exhaust fan an see what the temps are like. If they're too high for you, I'd try just one fan in the bottom (with HD and SSD on top) before trying 2 fans.

Modo
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Re: Fan Distance from Passive Card ?

Post by Modo » Mon Jan 24, 2011 4:32 am

You should be fine as long as you open a slot cover or two below the graphics card. The only real problem you can have with a fanless card is that it's cooked in its own heat. Opening the slot covers (if they aren't already open by design) gets rid of the dead air in the lower back of the case. With this, you can even do without any front intake, since a back exhaust fan would force enough air to come into the case through the bottom back intake.

wouterr5
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Re: Fan Distance from Passive Card ?

Post by wouterr5 » Mon Jan 24, 2011 9:52 am

It probably doesn't need much airflow, yet only a front-fan might not be enough:
When we look at temperatures the GT 430 performs well in a case with good airflow. It should be noted however that the card does require good ventilation and air moving past it as when this is removed we see temperatures reach well over 90°C.
from: http://www.hardwareheaven.com/reviews/1 ... cking.html

My case looks very much like the one you're looking at, and with only the front-fan at 1100 RPM my GPU can get to 80 degrees easily, with a 500 RPM fan directly attached to it it doesn't get past 35 degrees, so fans near it are definitely more efficient.
Also, i hope that 65 watt quad is one you've lying around, as there are much better options on the market nowadays (i5 2300) :o

whispercat
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Re: Fan Distance from Passive Card ?

Post by whispercat » Mon Jan 24, 2011 5:30 pm

wouterr5 wrote:It probably doesn't need much airflow, yet only a front-fan might not be enough:
When we look at temperatures the GT 430 performs well in a case with good airflow. It should be noted however that the card does require good ventilation and air moving past it as when this is removed we see temperatures reach well over 90°C.
from: http://www.hardwareheaven.com/reviews/1 ... cking.html

My case looks very much like the one you're looking at, and with only the front-fan at 1100 RPM my GPU can get to 80 degrees easily, with a 500 RPM fan directly attached to it it doesn't get past 35 degrees, so fans near it are definitely more efficient.
Also, i hope that 65 watt quad is one you've lying around, as there are much better options on the market nowadays (i5 2300) :o
Thanks for relating your experience with a similar case. Yeah, I had a feeling the front intake fan alone wouldn't keep the card as cool as I'd like it to be (below 60 degrees).

In the two front fans case I don't think I'd want to add yet another fan inside. And I really need only one fan (if that), to cool the HDD anyway. So I'll probably fall back on frenchie's idea of placing a fan closer to the v-card inside a different case instead... like this PC-7FN with only one front fan:

Image

The only question is where to place the fan, since there appears to be nowhere to mount one close to where the Zotac would sit (behind the ODD or HDD cages?) Is it possible to rig something up close to where the video card would be aligned on a uATX ? (I presume the card would ride slightly higher up in the case due to the smaller board size).

Image

Image

(Incidently, my quad core 2 duo board is in my present system and about two years old, but it suits my needs (except for the fact I now need a video card to upgrade from onboard graphics).

frenchie
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Re: Fan Distance from Passive Card ?

Post by frenchie » Mon Jan 24, 2011 5:58 pm

Use zip ties to put it where you want : remove the HD trays you're not using and zip tie it behind the HD bays. I would leave at least 2 cm between the HD bays and the fan if you can, using some kind of spacer.
If that doesn't work with your case, forget about a front fan and zip tie the fan directly on the card (Nexus @5V is inaudible inside a case and should provide enough cooling)

Side note : your HD will probably be fine without direct airflow from a fan

whispercat
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Re: Fan Distance from Passive Card ?

Post by whispercat » Mon Jan 24, 2011 7:36 pm

frenchie wrote:Use zip ties to put it where you want : remove the HD trays you're not using and zip tie it behind the HD bays. I would leave at least 2 cm between the HD bays and the fan if you can, using some kind of spacer.
If that doesn't work with your case, forget about a front fan and zip tie the fan directly on the card (Nexus @5V is inaudible inside a case and should provide enough cooling)

Side note : your HD will probably be fine without direct airflow from a fan
Thanks. I didn't realize one could tie a fan directly onto a card. Any possibility of the plastic zip tie or anything on the fan itself melting?

frenchie
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Re: Fan Distance from Passive Card ?

Post by frenchie » Tue Jan 25, 2011 7:06 am

If the zip tie melts, you have a big problem :D !!!
A lot of zip ties are made of Nylon that melts at around 200°C (can be much higher depending on the type of nylon), so I don't think you have to worry about that ;)

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