HAF 922 (interesting) side panel fan question.

PoisonWolf

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Hi guys,

I have a weird unorthodox question about the HAF 922's sidepanel question. For those of you who might not know, the side panel allows you to place either a 200mm case fan or 2x 120mm case fans. Now, due to my current parts, what I have is that the CPU's heatsink fan is blowing air towards the side panel (sitting directly above the CPU), while my GPU has a fan that is acting as an intake and pushing air out into the rear of the case through a plastic tunnel (HIS Radeon, this fan is facing dowards). The GPU is aided in its cooling with the help of my PSU that is blowing upwards in the case.

If you already have a glimpse of how it looks like now, my question is whether it is better to have 1 200mm acting as an exhaust (intake directly counters the effect of the CPU heatsink fan), or should I have 2x 120mm fans where the bottom fan is acting as an intake (blowing to the GPU as well), while the top acts as an exhaust (help push more air away from the cpu to aid in the CPU cooling)?

I know this is weird, googling didn't turn up anything so I thought I'd ask.

Any thoughts?

Cheers.
 
Solution
The classic case fan configuration is cool air is pulled in by case fans located at the bottom front of the case and hot air is blown out of the case by fans located at the top rear of the case. Fans on the side panel are used to blow in supplemental cool air. Depending on their location on the side panel those case fans are used to help cool either the video card or cpu.

Now, about that power supply. Modern atx power supplies do not blow into the pc case. They are designed to pull in warm interior air and blow it out the back of the case. That goes all the way back to the development of the atx standards. At the time cases did not have any fans. The only fan in a case was the psu fan. The atx standard specified the power supply should...
The classic case fan configuration is cool air is pulled in by case fans located at the bottom front of the case and hot air is blown out of the case by fans located at the top rear of the case. Fans on the side panel are used to blow in supplemental cool air. Depending on their location on the side panel those case fans are used to help cool either the video card or cpu.

Now, about that power supply. Modern atx power supplies do not blow into the pc case. They are designed to pull in warm interior air and blow it out the back of the case. That goes all the way back to the development of the atx standards. At the time cases did not have any fans. The only fan in a case was the psu fan. The atx standard specified the power supply should be located near the cpu so it could help exhaust hot air. As cpu's became more powerful and ran hotter and hotter case fans were installed.

Are you positive your psu is blowing air into the case?
 
Solution

PoisonWolf

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Guys,

Hmm, thanks for the prompt reply. Now you've got me confused, lawl. This is the power supply (link here). I don't know, I could have sworn that when I placed my hand inside while the thing was running, it felt like air was coming from it. However, I've also just placed a piece of tissue paper on the rear and it seems that the tissue paper is moving away from it, damn my friend for telling me otherwise! Haha.

Regardless, even with the PSU sucking air out, doesn't it still make sense to have the bottom 120mm acting as an intake, to bring fresh air for both the GPU and PSU, while the top 120mm acting as an exhaust to aid with the CPU cooling (which is blowing air in the same direction)? Oh, and another silly rationale I had for this "odd" idea of fan directions was due to the fact that hot-air rises.

I was just wondering, because I initially wanted to get a 200mm fan, but this dilemma has made me consider 2x 120mm fans instead. Any thoughts on this?

Once again, thanks for the prompt replies, and I appreciate the detailed posts!

Cheers.
P.S. On a tiny sidenote, as long as a PSU is touching any part of the case (e.g., when it is screwed to the case), the case is grounded, yes?
 
Excellent choice in power supplies. I use Corsair power supplies too.

Are you asking about fans on the side panel? If so, then the it should be used as an intake fan so it can help cool interior components. If the side panel can accomodate two 120mm fans, then both should be intake fans. Personally I would go for one large 200mm fan. It can blow in just as much air as two 120mm fans and do it at lower rpm so it's a bit quieter.

Yes, the pc case is grounded through the power supply.
 

PoisonWolf

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Guys,

Thanks, I appreciate the input. I finally realized how silly I've been all this time. I kept assuming that the CPU fan was blowing air out, it's actually blowing air onto the CPU. Lawl.

I've been getting air directions mixed up the entire day.

Okay, a 200mm fan it is!

Cheers.