# fan configuration



## struby (Jul 8, 2010)

I have my cpu fan, and 5 fans around my pc:

3 IN fans: back bottom and front

2 out fans: top

I have the 2 top fans and the bottom fan on a controller, which was more something I wanted to do than needed, I'm not overclocking or anything like that at this point, if anything I felt like I wanted my gpu to be cooler, it idles at like 51-54 C. Anyway, the fans even up all the way, don't really make a difference, but I was wondering if that setup was reasonable. The top two fans are covered with a mesh that came with my case, I was wondering if I should still have that on, even if those fans are blowing out. I was considering flowing air in through the top also, but I thought maybe that mesh would make the air flow less in that case. 

this is my case:

http://www.newegg.com/Product/Product.aspx?Item=N82E16811121096


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## shotgn (Aug 10, 2008)

I have found that positive pressure to be more effective, more air in than out, but others would disagree saying more fans blowing out than in(personal choice imo)

In my setup I would have the front in and rear out..thats it, i find that extra fans cause turbulence and the air flow disrupted.

What are your specs?


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## struby (Jul 8, 2010)

I have a phenox x4 955 BE on stock cooler
hfx 5770 hd
4 gigs ram
gigabyte mobo
500 gb hard drive (Seagate Barracuda 7200)
OCZ 550 Watt psu
case is in first post

I only have 1 fan spot in my case on the bottom in front of hd, so like I say below, which is something I posted in another forum I just pasted in, I feel inclined to pull in through the back and out the front, but the turbulence thing kind of crossed my mind, I feel like I should draw a diagram of the inside of my case and ask again sometime soon, maybe tonight or tomorrow.


I posted this somewhere else also, so I wanted to add it:

well only my bottom intake has a filter. Ideally I would like to pull air in through the top and back (and maybe bottom), and push it out through the front 1 (2if I rig another sometime) (and maybe bottom). Meaning the bottom could be either, I doubt it does much anyway unless I boost the tower up.

I say ideally meaning that would blow air at my gpu from sides, and have 3 fans blowing on my cpu. That doesn't mean what I think is ideal is what's best.

The problem is I feel like I need a fan blowing on my hard drive, which is what my front fan is doing now. My hard drive has no heat problems to my knowledge, but I just feel like that's the right things to do...?

Another fan in front would take up bays, but probably bays I will never use, and I would have to rig it.

Is 51-56 hot for gpu idle, i'm sure it heats up while gaming also.


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## shotgn (Aug 10, 2008)

That is warm for idle, your 550w psu can run your card but not for long as i feel your psu might be straining to keep up..which would cause heat issues on the gpu.

Can you get into bios and post your temps and voltages?


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## struby (Jul 8, 2010)

I forgot to get the bios stuff, but:

Here is a drawing I quick whipped up for my case.

Blue is IN fans

Red is OUT fans

The thin red arrow is my GPU exhause (I think it is out the back)

The thin red rectangle is my psu fan, which I did not know worked as an exhaust until now. I thought my psu was solid on the bottom, in fact I kind of still think it is, but I should have a look when I get home.

Notes: all designated fan spaces on my case are covered in fans, so that's where those are located. There might be enough room in between the fan speed controller and the bottom fan for another fan if I rigged it, but I don't think it is meant for a fan, and it might take away all or all but 1 of my remaining bays to put a 120 mm fan there. And I would have to order another fan.

The only fan with a dust filter on it is the bottom fan next to the psu, as it is on carpet.

the gpu fan is on the lower side, and the board is on top in the pic

 

Looking at this now, it seems dumb, but how would you guys suggest doing it, keeping in mind that another fan could be an option. My GPU idles around 55 C, my cpu around 39 or 40 C, and my system temp around 44 C.


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## gcavan (Aug 13, 2009)

The fan in your psu draws air in and pushes it through the supply and out the back. I would turn the supply over so it is drawing cool air through the bottom of the case. Mind you this may create a wiring issue.
The fan on the back is really doing nothing. Any air it draws in (which is mostly pre-heated air rising off the power supply) is immediately sucked back out by your top exhausts. Turn it around so that it exhausts also.









Whether or not you reorient your fans, I suggest you place your computer on a bit of 1/2 inch plywood or something similar the size of your computer's footprint. This will not eliminate the dust but will limit it and, more importantly, will ensure the fan intakes are not blocked by the carpet.

P.S. You are not going to have an issue with positive/negative pressure as almost the entire side panel of your case is screened.


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## shotgn (Aug 10, 2008)

thanks for pointing that out gcavan, i didnt notice the side was screened


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## struby (Jul 8, 2010)

yeah that all sounds correct based on what my psu looks like now that I'm looking at it. It pulls air in and sends it through the grate on the back. I'm going on vacation for a week, during which I'm probably going to rma my hopefully problem causing mobo, so for now I probably won't find anything out or do anything, I'm a little worried about the turned over psu, is that safe and all? I guess it would mount that way, but ur right it could cause wiring issues then I'm not sure depends how it turns. I'm also worried about the psu resting on the fan grate, and not pulling in cool air due to the carpet, so I guess I would, as you said, lift it, which I was considering anyway.


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## llacrossedude7 (Jul 31, 2009)

I personally have a positive case pressure set up and it works great I idle at 18C and max anywhere from 28-30C at 3.76GHZ if you want you can look at my rig on how its set up.
http://www.techpowerup.com/gallery/2699.html


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## Tyree (May 10, 2009)

Try one fan in front blowing in and one fan in the rear blowing out and check your temps. Add fans one at a time and continue checking your temps. Too many fans can be as bad, sometimes worse, than too few.


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## struby (Jul 8, 2010)

my case does have a vent under the psu, but I can't decide whether to flip it or not, I think it would be better the boost the pc up a couple inches either way, but if I do flip it, should I put a screen there, or will that restrict air flow to the psu, I feel like those screens, or at least the ones that came with my case, restrict air flow.


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## gcavan (Aug 13, 2009)

Anything placed over an opening will restrict air flow to some extent. Its a trade off: no filters means highest volume of air but also more dust inside; . Since you have a carpeted floor, you definitely want some sort of filtration on your bottom intakes. Easiest way to raise your comp off the carpet, place it on a piece of plywood or MDF the same size as your computers footprint.


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## magnethead (Mar 18, 2006)

^ What he said

I personally run my Antec 900 as a negative pressure case for standard computing, and switch to a positive pressure mode for gaming. The CPU and top fans are always on, but I switch the front, rear, and side fans on via controller. It doesn't change the CPU temp much, but HDD temps go down, and GPU temps stay stable.


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## struby (Jul 8, 2010)

I'm mainly worried about the gpu, I think I'm going to raise the case with 4 feet, I don't understand the footprint comment, unless you just are refering to getting it off the carpet by putting wood under, which I might do in addition to the feet.

I mainly think my GPU temps are a little high, I am not changing anything now because my mobo is in RMA process. I don't want to flip the psu cuz I'm worried it will suck in dust, or not enough air if I dust filter it. my gpu is right below my psu, so I feel like blowing air onto my GPU would just counteract the psu pulling air in, but I want to cool the gpu.


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## gcavan (Aug 13, 2009)

By footprint, I mean the space the computer takes up on the floor; probably about 8 inches by 18 inches.


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## magnethead (Mar 18, 2006)

I like their suggestions. Set it on a piece of wood (or even cardboard) so that the feet have it set, should be like 1/2 to a full inch between bottom of case and the wood/cardboard. IF room permits, you can flip the PSU so it's fan down, as long as it's not facing direct carpet, you should be fine.

Dust filters are a love/hate relationship. My Antec 900 doesn't have them, and you can tell if you look inside. My mom's Antec 300 has them, and I'm cleaning them every 2 weeks, but the inside is FAIRLY clean. Some dust still gets through, but nothing like my 900. That's also considering the animals don't come in my room that often, but they all sit next to mom at the computer (we have a dog and 4 cats).

My 9800GTX idles at 55C (fans off), and gets to about the 60's in game (fans on) and low 70's in game (fans off). HDD's are 32C with the fans off (negative pressure) and 30C with fans on (positive pressure), but that's because the fans blow directly on them. CPU sits between 55-60 in speedfan, never exceed 60 (per speedfan- BIOS reports differently). 

When my card was under warranty, for kicks and grins, i shut the GPU fan completely off with Rivatuner. The card got to 100C in game, and never artifacted driving 2 DVI monitors, that was a good year and a half ago. It's pretty hard to kill a GPU with heat, i've deducted.


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## struby (Jul 8, 2010)

all very good, so would you say a two inch boost up is overkill, I'm moving to school and my apartment is cramped, it could be in a somewhat tight area, I'm going to try my best, it might sit on top of my old desktop.

If I were to flip the psu and it got dusty, can a psu be cleaned out, or do I just blow compressed air into it until the dust makes it's way out?

All sounds like very good advice guys thank you. Your temperature information helped put me at ease a bit.

-Andy


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## gcavan (Aug 13, 2009)

It will collect dust, no matter what you do. A blast of air once a month or so should keep it clean. And really that's all you can do without voiding your warranty. Also, make sure to dust/vacuum the floor under the computer often.
A half inch clearance would be plenty.


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## struby (Jul 8, 2010)

alright sounds good thank you for the input.


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## WereBo (Apr 5, 2008)

If you've got a couple o' sturdy boxes to stand the PC on, the case-top can make a very useful 'mouse-rest' area - The extra height also reduces the 'floor-dust intake' to practically zero too :grin:










I used the 2 boxes that my HDD's came in :laugh:


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## struby (Jul 8, 2010)

Thanks, I might try to go with something wood that I can paint black, but I like the simplicity. I also have issues with desk height so maybe that would be an idea for a solution.

Is the gardening book an integral part of the stand?


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## WereBo (Apr 5, 2008)

Hehehehehe..... Naaahhh, it's just a handy place to keep the book to browse through, when I'm waiting for some pages to load, DVD's to burn/whatever :grin:


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## struby (Jul 8, 2010)

WHAT!? I already went out and bought a gardening book and 2 hard drives so I could use the boxes, what am I supposed to do now!?

haha, thanks man, peace


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