[SOLVED] How to configure the Mid HDD fan inside the case?

cemster

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Hello,

I have a Cooler Master Cosmos II case.

I am not sure how to configure the mid HDD fan. Should I blow towards the HDDs or the opposite?

Ideally, I want to cool down the HDDs, but I am worried to blow hot air from the case.

I do have three outtakes: 2 x 120 mm fans on the top and a 140 mm rear stock fan. And 2 x front fans: the 140 mm stock fan and I added a 120 mm fan below the front fan. They blow directly onto the top HDD cage. I also installed 2 x 120 mm bottom HDD fans. They blow onto the bottom HDD cage from the side.
So, the one last fan I want to install is the mid HDD fan marked with the red arrow. (please check the link) https://im.ge/i/TZJ1m

But I am confused about how I should configure that one. What would you suggest?

Thank you
 
Solution
That is hot but, depending on the model and manufacturer, may still be within normal operation spec.
If the ones at the top have a higher CFM you could try replacing the front fans with these.

However, be sure to do all these moves one step at a time testing for hours to get a feel for the benefit (if any). Worse thing you can do is swap around everything in one go.

Edit - do you have a dust filter up front? If yes try removing it. You'll have to clean out your case much more frequently but it could give you a few degrees celcius drive temp difference.
Front fans should be intake. Where are the 2x120mm bottom HDD fans getting their air from? Are there holes in the bottom of the case...?
Personally, I'm not a huge fan of top-of-case exhaust fans. I prefer rear case fans so my VRMs get at least a little airflow lovin'. Too many fans create vortices which isn't good for airflow or cooling.

Go ahead and add the front intake. If the 2x120mm bottom HDD fans are just grabbing and swirling around air from inside the case remove them. I would even try unplugging the top fans to see if you get some improvement in airflow out the back.

Edit - Didn't see the link at first. Okay those bottom side panel fans are fine as long as they're drawing air from outside the case. The one you point to could be intake (pulling air through the drives) but I think it'll create vortices around the middle of your case more than anything else. I would remove it. I would also still try to disconnect the top fans to improve airflow from front to back.
 
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cemster

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My CPU is 11900K, so it's gonna run quite hot. Not to mention I have 10 HDDs total.
The back exhaust fan is a stock fan and the efficiency is not necessarily admirable. Hence the two top exhaust fans. I have, in total 3x 120mm fans and also a 140mm stock fan for intake.
So, the two top exhaust fans seem like a good balance for all those intake fans. no?
 
Those top fans could be causing an efficiency issue for your Noctuas. They're too close to your CPU fans and are fighting for the same air. Having an overall positive air pressure is preferred and the rear case fan is getting some 'help' from your Noctuas anyway.
It's just a recommendation to try. It's simple to unplug and test.
 
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cemster

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Okay. Thanks a lot.
I just bought those fans so it is kinda heartbreaking :)

Actually, the pannel fans wouldn't help much for the HDDs, since they are not aligned with HDDs.
I wish I had a better way to cool those HDDs. Those 5 HDDs on the top shelf get really hot. Because they get over 50 celsius with that front stock fan alone. Do you think, if I upgrade the front stock fan with a better & faster fan, would that help?
 
That is hot but, depending on the model and manufacturer, may still be within normal operation spec.
If the ones at the top have a higher CFM you could try replacing the front fans with these.

However, be sure to do all these moves one step at a time testing for hours to get a feel for the benefit (if any). Worse thing you can do is swap around everything in one go.

Edit - do you have a dust filter up front? If yes try removing it. You'll have to clean out your case much more frequently but it could give you a few degrees celcius drive temp difference.
 
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Solution

iPeekYou

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Okay. Thanks a lot.
I just bought those fans so it is kinda heartbreaking :)

Actually, the pannel fans wouldn't help much for the HDDs, since they are not aligned with HDDs.
I wish I had a better way to cool those HDDs. Those 5 HDDs on the top shelf get really hot. Because they get over 50 celsius with that front stock fan alone. Do you think, if I upgrade the front stock fan with a better & faster fan, would that help?

Don't run the fan right against the drives; they will get warm from the fan motor alone.

My case has rails for front mount fans and on the bottom are the 3.5" drives. I found that moving the bottom front fan right over the drives increase temps by 8 deg C on idle alone. I moved the offending fan upwards so that the fan motor is away from the drives and only the bottom half covers the drives. Cools my HDDs under 45 even during defragmenting.
 
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