SEARCH

The How-To Geek Forums Have Migrated to Discourse

How-To Geek Forums / Build Your Own PC

Case Air Flow

(11 posts)
  • Started 6 years ago by Dannzzigg
  • Latest reply from raphoenix
  • Topic Viewed 5667 times

Dannzzigg
Posts: 5

I have an older case that I'm going to be using to house my new build. Case Specs and PIcs

It currently has two 80mm fans- 1 blowing in the side and 1 blowing out the back directly under the PSU, as well as the PSU's own fan which blow out the back as well.

I have 3 120mm fans en route fans

as well as a top venting PSU PSU

I obviously plan on cutting a hole for the PSU top fan, and I was also planning on changing the side panel to a solid window and cutting out holes for one or two of the new fans to blow in from the side.

I've read some here and there about fan setup, and I'm trying to determine the best use of the fans I have available. Would it be worthwhile to cut an additional spot in the top of the case for a 120mm exhaust fan there?

Should I move my intakes to the front, blowing over my HDDs?

Your suggestions are welcome...

Posted 6 years ago
Top
 
raphoenix
Posts: 14920

Dannzzigg,

Welcome to The HTG Forums.
You Do Not Need to Cut a Hole for a Top Fan.
The Large Side Fan will stall your CPU cooling solution plus puts a positive pressue in the case.
====================================
(3) post combined as to Fans.
From my reply to another poster.
SUMMARY:
1. Case pressure should be equalized or neutral.
2. Front Case Fans should blow into case through Filters.
3. Rear Case Fans should exhaust out of case.
4. A large side case Fan can Stall CPU air cooling solution.
5. Fans should run Constant RPM, High Volume CFM.
6. All Bios speeds and temps are not exact because of Off-Sets.
7. PS should have (2) Fans.
======================
From my reply to another poster.
***** Have filters on front case fans so if filters get dirty, it's like fans sucking against a wall and back case fans will get starved for air. This will result in a negative case pressure due to exhaust fans but they will begin to stall so general air flow volume will decrease.
I Use (3) fans in front case.
(1) in front of EACH HD Cage to cool HDs and (1) at BOTTOM of case for general volume make up air increase.
(2) on back of case for exhaust.
PS has (2) fans to pull air up and out plus cool PS.
Remember CPU fan has do its job but not be stalled by air flow going in circles or every-which-away. Similar to Eddie Currents in electrical analogy.
======================
Moral of This:
Keep Filters Clean.
Balance air inflow and outflow in constant straight or up and out PS (smooth) streams.
Keep air flow constant by (not) varying fan speeds.
Remember all components are putting off heat and only being cooled by ambient air temp/air flow.
The old fan noise issue has been around for as long as I can remember so no use to even worry over such.
=======================
From my reply to another poster.
A Tip:
Purchase a case lot (10) or (12) to a Box of Ball Bearing Constant High Speed, High CFM Fans.
(Cheaper) in long run plus the Box is considered as (1) shipping charge.
Edit: About $4.00 bucks or less per fan.
Your case probably has several brackets for more than (1) fan.
They don't pull much power so PS will not be an issue.
My cases have (6) brackets for 120MM fans.
Fans get "gunked up" and need to be replaced (often).
=====================

Kindest Regards,
Rick P. ♥ :)

Posted 6 years ago
Top
 
Dannzzigg
Posts: 5

I'm both surprised and confused about "You Do Not Need to Cut a Hole for a Top Fan"... does it still blow the air out the back? I thought a PSU like the one I mentioned was designed for a case like the Antec 900, with a top vent.

Also, if mounting the fans on the front of the case is out of the question, would the next best thing be to mount them on the side but lower, away from directly putting air into the cpu fan?

Posted 6 years ago
Top
 
lukepools
Posts: 7

FIlter? Is this something like a air filter for your house AC?

Posted 6 years ago
Top
 
Dannzzigg
Posts: 5

The fans I plan on using have foam filters over them that can be removed and cleaned in the sink. You can also buy filter assemblies to retrofit existing fans.
FAN FILTERS

Posted 6 years ago
Top
 
ScottW
Posts: 6609

Dannzzigg, hello. That link to the case at TigerDirect says: "THIS ITEM IS CURRENTLY UNAVAILABLE". Have you checked into that? I tried to find more info about the case, but I don't see that same case at powmax.com or any other retailer.

If you do get that case, you are in for a lot of modding, but it seems that you are prepared for that. Certainly putting a top-exhaust PSU in a rear-exhaust case means that you should definitely cut a top hole for it. You don't want that fan venting inside the case, especially right next to the case wall. From what I'm reading at TigerDirect, it says the case has two 80mm fan ports and one 120mm fan port. I'm not sure which is which. Certainly you should set the rear fan as an exhaust. If there is a front mounting for a fan, you can put one there as an intake.

The side intake port is a controversial item. My opinion is that the best use of a side intake is for a snorkel to bring ambient air to particularly hot parts, such as the CPU or GPU. Adding an intake fan on the side is where there is much disagreement. It seems like a way to inject more ambient air into the system, however it will also disrupt the airflow from front to rear. It will cause some turbulence and it will increase the pressure inside. If you must mount a fan there, I would suggest that you lock it on the lowest possible speed.

Posted 6 years ago
Top
 
Dannzzigg
Posts: 5

I already have the case.

There is no 120 mm fan port, so the link I provided may be for a slightly different version.

So... it seems the best thing is going to be to cut a port (or two) in the front then? I'm not sure how much room there is. Is it normal to have your intake fans blowing right over and between your HDDs?

Posted 6 years ago
Top
 
ScottW
Posts: 6609

Alright, I see what you are doing. So, why are you getting 3 120mm fans if there are no fan ports that size on the old case? I can see you mounting one as an intake on the side, but if the rear exhaust port is 80mm, that's no place for a 120mm fan. In your first post, I think that you were discussing a second exhaust port in the top of the case in addition to the PSU exhaust port. If so, I would recommend against that. A 2nd top exhaust would have to be farther forward and would be exhausting air that had not yet passed over the hottest components. It would also be transverse to the normal front-to-back flow of air.

In response to the question, "is it normal..?" I would say that there really is no "normal" when it comes to air cooling. However, we can talk about usual. The usual intake setup is with vents on the side of the front bezel. Sometimes these are long vertical slots down the left and right side or horizontal "gill" slots, like the Alienware cases. It is less common to see a front intake fan in the center of the front bezel. Usually there are drive bays in there instead. Just looking at the case you linked to at TigerDirect, there are 4 internal 3.5" drive bays at the bottom front of the case and no obvious fan mount in there. If the case is designed to intake air through slots around the perimeter of the front bezel, I would not recommend cutting an intake port in there or mounting a fan there.

If you have the PSU fan exhausting out the top, the rear fan exhausting out the rear and a side fan (turning slowly!) for intake on the side, the natural flow of air should pull ambient air in through the front of the case to flow over the drives for plenty of cooling there. The front-to-back airflow, pulled by the rear fan, will draw air over the CPU, motherboard chipset, and adapter cards. The side port intake will allow cooler ambient air to mix with the front-to-back air current just before it flows over the hot components. The PSU, as is often the case, will be taking in hot air from inside the case and exhausting it out. That's not good for cooling the PSU components, but it's good for the air flow in the case. The Antec P180 series addresses this concern by providing a separate air chamber for the PSU.

Posted 6 years ago
Top
 
raphoenix
Posts: 14920

Dannzzigg,

You are attempting to use, possibly, the (Worst) computer case product ever built.
(Read) the reviews of the case in your link I.E. "Fried Mothers Boards", Etc.

Recommend you purchase a more (Standard) case for your new build and investment.
Suggest Antec Cases and Enclosures for their quality plus one can purchase Spare Parts.
http://www.antec.com/ec/
Of course, each may run their own machines as they wish.
Good Luck.

Kindest Regards,
Rick P. ♥ :)

Posted 6 years ago
Top
 
Dannzzigg
Posts: 5

Thanks for the input. I'm pretty much stuck with case I have, and I'm trying to make the best of it. My original plan was to replace the single 80mm side fan with at least 2 of the 120mm but as I have been reading, that's apparently a great way to fry my CPU.

I'm looking at the front of the case now, and it looks like I can cut a port for a front intake fan without too much work. It should fit between a bottom mounted HDD and my top mounted 5.25's. I won't be able to use the smaller bays though, but I fiogure some compromises are going to be necessary when using "the worst case ever made" :)

Maybe I'll hack this one up so badly I'll have no choice but to start with a new one :)

Posted 6 years ago
Top
 
raphoenix
Posts: 14920

Dannzzigg,

You are welcome. We just didn't want to see you "fry" your New Build.

If you think about it, a Good Case will (out last) many new builds so if if your budget allows, would urge you to look at the Antecs as me and ScottW suggested.

This Antec old Tower is running its 3rd build now and if I can afford it, maybe will make one last build (X58) machine in it.

I like the Antecs because one can always order spare parts like more fan brackets and such.
=============
If you call them, they may have Brand New Cases which may have paint blemishes and will sell you a new case for half price or less. They are good folks to deal with. Don't think I mentioned this before.

Kindest Regards,
Rick P. ♥ :)

Posted 6 years ago
Top
 



Topic Closed

This topic has been closed to new replies.