How do you determine which way an airflow in case should go?

[podkall]

I know sites have an aifrlow diagram which clearly gives you idea how to mount your fans but when there are 6 spots with arrows and than 2 without any direction arrows?

 

Is it like suppost to go from bottom to GPU or is it user preferance and it can go other way too for some reason?

 

I'll put a picture. Could you tell please?

 

Thanks.

[Radium_Angel]

4 minutes ago, podkall said:

I know sites have an aifrlow diagram which clearly gives you idea how to mount your fans but when there are 6 spots with arrows and than 2 without any direction arrows?

 

Is it like suppost to go from bottom to GPU or is it user preferance and it can go other way too for some reason?

 

I'll put a picture. Could you tell please?

 

Thanks.

Hot air rises, so personally, I'd that those two that have no directional arrows, and point those fans upward, so ultimately all the hot air goes out the top.

 

[Tristerin]

Literally however you want.  

 

There is positive, neutral and negative pressure created (depending on how you set up your fans) and each setup has pro's/con's in terms of dust and temperatures that is unique to the case layout in regards to airflow.

 

My suggestion - try them all.  I do when I get a case (Ill even do all exhaust and create a super negative pressure environment).  When I find a great case that does a neutral pressure that still achieves good temps (hard to find imho - usually you trade better temps for harder to get neutral pressure) its usually the cleanest 1 year from build date after running for a year in terms of dust intake.  Had 1 PC run for 1 year and when I cracked it open...it was pristine clean on the inside.  Terrible temps the whole time lol.

[aDoomGuy]

Well... I do not recommend having two exhaust on the top, especially not if the CPU has an air cooler because the top fan will steal air from the CPU cooler. If you have AIO that's not so bad but maybe there will be less fresh air coming over the VRM area.

 

I use 3 front intakes, 1 top intake infront of the CPU and 1 exhaust. Simple as that.

 

 

[podkall]

1 hour ago, aDoomGuy said:

Well... I do not recommend having two exhaust on the top, especially not if the CPU has an air cooler because the top fan will steal air from the CPU cooler. If you have AIO that's not so bad but maybe there will be less fresh air coming over the VRM area.

 

I use 3 front intakes, 1 top intake infront of the CPU and 1 exhaust. Simple as that.

 

 

Idk man if fan steals air from the cooler it means the fan is grabbing the hot air away from CPU away unless you mean that the fan grabs the cold air before it gets to cpu which I understand

[aDoomGuy]

48 minutes ago, podkall said:

Idk man if fan steals air from the cooler it means the fan is grabbing the hot air away from CPU away unless you mean that the fan grabs the cold air before it gets to cpu which I understand

Yes the latter. It is more preferable to have intake infront of the CPU tower or exhaust behind it (exhaust behind will also help VRM).

[AngryBeaver]

16 hours ago, aDoomGuy said:

Yes the latter. It is more preferable to have intake infront of the CPU tower or exhaust behind it (exhaust behind will also help VRM).

For the setup in that picture I would say that would be an optimal setup. In the best case you want to create a nice wind tunnel effect. In the end though the goal is just air exchange. All of the talk about the front top fan stealing air is mostly nonsense. As a single 120 out just nullifies a 120 in. The top fan cannot move more air than another intake fan of similar size and rpm. So the air flow through even an air cooler would still be more than sufficient. The main goal is to keep the air temp in the case close to ambient. So it is more about how well that is happening.

[LogicalDrm]

Inside PC case, only fans move air. If air molecules are out of any fans area of effect, that is "hot pocket". "Hot air rising" only happens with natural convection and if there's nothing else moving air. So inside PC case that rarely happens as there should always be a fan to move the air. Outside of PC case? Whole another story.

 

If you want to start learning on how airflow should be setup, start by components which have fans and where you can't control the way fan blows. Meaning GPU and PSU. Latter is easily taken out of equation by letting it intake from below the case and blowing hot air out of its back. Now there's only GPU. And with it, things are bit tricky.

 

There are 3 types of GPU coolers.

• Blower, which has 1 intake fan and card blow hot air out of the case directly.
• Open-air, which has 1-3 fans blowing towards PCB and then exhausting hot air all over the case.
• And there's the Nvidia's new cooler which has one intake and one exhaust, intake blowing towards PCB and exhaust blowing towards CPU cooler.

 

Then CPU cooler. Here you can have some input. But lets list options:

• Downdraft. Classic example being stock cooler. The point is that fan is pushing air down towards IHS and then all over the case.
• Single tower. One single tower and usually single fan. Default configuration is fan blowing air through heatsink and towards rear. On some older AMD sockets you couldn't change orientation of the cooler. So you could only choose between push or pull. On modern sockets you can also select between vertical (default) and horizontal positioning, if your RAM allows it.
• Dual tower. Same as above, but with 2 heatsinks. Notable coolers being NH-D15 and Dark Rock Pro 4. With these you usually can't change orientation since they are so big. You get 1-2 fans, and can add 3rd with minor improvement for performance.
• AIO. Anything from 120mm to 360mm. I don't consider custom loops since there are things to consider which will make fan placements irrelevant. In this category your case, and which unit you choose limits the options most. The fans for the cooler aren't on CPU, but act as either intake or exhaust case fans. This does have effect on cooling. Of both CPU and GPU. In short, rad as intake will mean lower CPU temps, but if placed near GPU intakes, hotter GPU temps (compared to without rad). Rad as exhaust will mean hotter CPU temps, but might not effect overall cooling in the case that significantly.

So these are factors to consider. There are more, but those tend to be for specifics PC cases, specific room or case placement situations and other such things.

 

As said by others, best way to learn is to test yourself. In my previous case I had 200mm sidefan. And I tested almost all ways to use that mount. Fan as intake; no fan, but mesh; plexiglass window. I don't remember if I tested fan as exhaust, but if I would do it again, that would also be on the list. I learned that temp difference between fan and Windows was almost 10C, but between passive and Windows only 3C.

[podkall]

2 hours ago, LogicalDrm said:

Inside PC case, only fans move air. If air molecules are out of any fans area of effect, that is "hot pocket". "Hot air rising" only happens with natural convection and if there's nothing else moving air. So inside PC case that rarely happens as there should always be a fan to move the air. Outside of PC case? Whole another story.

 

If you want to start learning on how airflow should be setup, start by components which have fans and where you can't control the way fan blows. Meaning GPU and PSU. Latter is easily taken out of equation by letting it intake from below the case and blowing hot air out of its back. Now there's only GPU. And with it, things are bit tricky.

 

There are 3 types of GPU coolers.

• Blower, which has 1 intake fan and card blow hot air out of the case directly.
• Open-air, which has 1-3 fans blowing towards PCB and then exhausting hot air all over the case.
• And there's the Nvidia's new cooler which has one intake and one exhaust, intake blowing towards PCB and exhaust blowing towards CPU cooler.

 

Then CPU cooler. Here you can have some input. But lets list options:

• Downdraft. Classic example being stock cooler. The point is that fan is pushing air down towards IHS and then all over the case.
• Single tower. One single tower and usually single fan. Default configuration is fan blowing air through heatsink and towards rear. On some older AMD sockets you couldn't change orientation of the cooler. So you could only choose between push or pull. On modern sockets you can also select between vertical (default) and horizontal positioning, if your RAM allows it.
• Dual tower. Same as above, but with 2 heatsinks. Notable coolers being NH-D15 and Dark Rock Pro 4. With these you usually can't change orientation since they are so big. You get 1-2 fans, and can add 3rd with minor improvement for performance.
• AIO. Anything from 120mm to 360mm. I don't consider custom loops since there are things to consider which will make fan placements irrelevant. In this category your case, and which unit you choose limits the options most. The fans for the cooler aren't on CPU, but act as either intake or exhaust case fans. This does have effect on cooling. Of both CPU and GPU. In short, rad as intake will mean lower CPU temps, but if placed near GPU intakes, hotter GPU temps (compared to without rad). Rad as exhaust will mean hotter CPU temps, but might not effect overall cooling in the case that significantly.

So these are factors to consider. There are more, but those tend to be for specifics PC cases, specific room or case placement situations and other such things.

 

As said by others, best way to learn is to test yourself. In my previous case I had 200mm sidefan. And I tested almost all ways to use that mount. Fan as intake; no fan, but mesh; plexiglass window. I don't remember if I tested fan as exhaust, but if I would do it again, that would also be on the list. I learned that temp difference between fan and Windows was almost 10C, but between passive and Windows only 3C.

I have stock cooler (so blows towards cpu down the thing) My gpu has double fan that should be blowing through gpu and out the back of case at least I believe..

[LogicalDrm]

10 hours ago, podkall said:

I have stock cooler (so blows towards cpu down the thing) My gpu has double fan that should be blowing through gpu and out the back of case at least I believe..

If it has two fans and it's not Nvidia's newest Founders, then it exhausts all over the case. But that's easy to check if you tell which model it is.

[podkall]

4 hours ago, LogicalDrm said:

If it has two fans and it's not Nvidia's newest Founders, then it exhausts all over the case. But that's easy to check if you tell which model it is.

https://www.gigabyte.com/Graphics-Card/GV-N1050WF2-2GD#kf

 

[LogicalDrm]

8 minutes ago, podkall said:

https://www.gigabyte.com/Graphics-Card/GV-N1050WF2-2GD#kf

 

Replying you in two threads gets confusing...

 

This image alone tells you that hot air will remain in case. Blower cards would have shroud covering them from all sides with single fan directing air in.

[podkall]

7 minutes ago, LogicalDrm said:

Replying you in two threads gets confusing...

 

This image alone tells you that hot air will remain in case. Blower cards would have shroud covering them from all sides with single fan directing air in.

if its going out the side than doesn't it matter, perhaps going with dragging cold air from top to bottom? since the fans are on top

[LogicalDrm]

3 minutes ago, podkall said:

if its going out the side than doesn't it matter, perhaps going with dragging cold air from top to bottom? since the fans are on top

Bottom exhaust, top intake? How are you going to get cool air to GPUs fans then? The fans are pointing down. That pic I posted is towards sidepanel. The air won't come out from PCB side (CPUs direction).

[podkall]

1 hour ago, LogicalDrm said:

Bottom exhaust, top intake? How are you going to get cool air to GPUs fans then? The fans are pointing down. That pic I posted is towards sidepanel. The air won't come out from PCB side (CPUs direction).

what do you mean how am I gonna get cold air to gpu? cold air enters from top, and gets exhausted from the bottom, literal bottom, isn't that one of the ways how it could be done?

[LogicalDrm]

12 minutes ago, podkall said:

what do you mean how am I gonna get cold air to gpu? cold air enters from top, and gets exhausted from the bottom, literal bottom, isn't that one of the ways how it could be done?

GPU fans are pointed to bottom of the case and intaking from there. Thats what I'm trying to point out. Also, unless you add fan in between the intake and exhaust, the air might not move enough at all.

[podkall]

2 hours ago, LogicalDrm said:

GPU fans are pointed to bottom of the case and intaking from there. Thats what I'm trying to point out. Also, unless you add fan in between the intake and exhaust, the air might not move enough at all.

wait... I'm stupid I thought my GPU faces up with fans.... oh my god, it gets confusing because you assume that it's on the side where the product is shown, ah everything makes sense now, so most GPUs grab the air from bottom. okay, good to know. thanks