Hello, I am putting a fan in the side vent of my new Antec 900, and was wondering. Should I postion the fan so that it pushes air into the case and onto the GPU/s, or should I position the fan so that it pushes air out of the case, over the GPU/s.

Thanks.

Hey; I generally put side-case fans blowing into the case, opposed to sucking out of the case. You would think that the way the fan is positioned would screw up the balance of airflow in the case if you suck air out the side. I have seen this done both ways (by people, AND manufacturers), and have not seen anything go wrong with either way. The only issue I did come accross one time was that there was a cone sticking inside of the PC with a fan sucking air out of the machine. This cone was positioned directly ontop of the CPU-fan.... This caused a suction between the CPU-fan and the side-case fan, and caused the CPU to overheat (god only knows why). We flipped the fan, and it worked fine.

As advice; I would position the fan blowing air into the case, take an ambient air temperature (record other compnent temps as well), and then try it the other way around and do the same thing. Whichever works better in your particular case is the way you should leave it.

I'm not even going to start on you putting a white/beige fan in a beautiful black case like the Antec 900... I mean it's like putting a beige
DVD+/-RW or DVD-ROM into a black case; this makes me lose respect for some of the nicest builds i've ever seen. I would have bought a black fan... (unless it's one you had lying around), they don't have any price difference!

God Speed.


EDIT: Just as a sidenote... Clean up the damn wiring in your case man, cleaning that up would alone give you a better temperature drop than adding a side-case fan. Jeez use some friggin' tie-straps.

Thats not my actual case, its just the first picture I found on the web, but the 900 needs moding to do much better anyway, and im planning on doing that. I also am puting a clear blue LED fan from Antec in it so I'm fine in that department.

OIC... Sorry for jumping to conclusions, at least you sound like you know what your doing. The clear blue LED will look sweet. Good luck, and upload a pic of your result.

God Speed

I have an Antec 900 case and I have three intake fans (two in the front, one on the side panel). The only exhaust fan I use is the massive one on top (since heat rises, why try to suck it out sideways?). The fan is blowing directly on my 8800 GTS 640, sound card, and controller, plus it provides additional air for the chipset cooler (on the 680i) and for the Ultra-120 eXtreme (which has its own 120mm fan).

Of all of the configurations I have used in keeping the temps low, that seems to make the most difference.

FYI, the side fan is one of the stock 120mm fans that came with the case (it had three of them) and is set to either low or medium, and the other fans are all set to low.

side fans should always be blowing into the case.

This way increases air flow to the CPU.
||----> ||---->
Case CPU
Fan Fan

Where as this way would be counter productive by sucking fresh air away from the CPU.
<----|| ||---->
Case CPU
Fan Fan

I had so much fun with that diagram I decided to do one of my own antec 900.
[+] CPU
1. 200mm top exhaust fan
2. 120mm rear exhaust fan
3. 120mm front intake fan
4. 120mm CPU cooler fan mount on the side of the heatsink opposite the top fan.

This setup gives my CPU great air flow even with all fans running on low and never goes above 45c.

/ \
|
1==

<---|| [+] <---||
2 ^ 3
=4

Strangely I understand that diagram all too well. Had a nice time typing that out? >_<

Thanks guys, and dg6464, no problem, I agree hole heartedly and you were right to correct me, if that was my case I would throw it at the wall. The Antec 900 is one of the most beautiful cases on the market, and that guy made it hideous with 1 fan lol. Nice diagrams, though purplerat's doesn't make much sense, but I get the idea. I only asked, because this is my first build and I am currently using a 7600 GT (I am planning to upgrade but I ran out of funds) on a 680i LT with a E6750. My 7600 GT idled at 60c in an emachine case, and is now idling at 46c, not sure why it did not drop further, I guess its because my cable management is TERRIBLE, but I will be modding soon.

This is how I have my fans set up

I would say that it depends on what gpu or how your gpu fan works. IMHO, higher end gpu's tend to produce lots of heat so it's better to have the side fan sucking hot air out rather than blowing air in that make the hot air circulate the area between gpu and psu (by that way hot air can't directly/effectively be exhaust via rear 120mm and top 200mm fan) not to mention the psu will suck warm air into it. I have tested it before with my previous 8800GTS. My 8800GTS temp even gone higher when I tried to position side fan to blow it rather than sucking air out of it. The way I position the side fan to blow in will not help to cool my 8800GTS since the whole card is covered by the hsf's plastic.

To my sense, the design of 8800's double slot fan is sucking air from its fan (fresh air provided by 2 intake front fans) and blow the hot air through the back but before it reaches the back, there are openings from the card itself and some of the hot air will slip out from here so the job of side fan exhausts hot air here is very effective.

For lower end gpu's that don't have the design of DSF or more opening gpu design or particularly for passive hsf gpu design, it's best to place the side fan to blow air in cause it will directly cool the gpu itself.

Finally, I would say before you try to figure out which way you would place your side fan, better have some test first before conclude. Place it in either way and have the temp recorded and compared. Hope this help.

Just my 2 cents...

I've tried allot of different fan configs in my case(s) to get the best temp I can get. So try things out to see what works best in your situation.

Now my latest case did teach me on lesson on the side fan. I use the "Aerocool AeroEngine II Mid Tower Case" which has a fake turbine fan in the front, but has the real fan behind it (140mm).

Since I brought a fan controller (Zalman ZM-MFC1) I did tests on it while waiting for my other parts. . o O (ya, I was bored)

Anyhoo... The fake fan turns from airflow, meaning it would stop if the airflow was being disturbed. So... to try to make this simple to understand:

Total fans - 4 (3/120mm 1/140mm fake fan in front of it)

1) I turned all the fans down CPU/Front/Rear(side fan was on a toggle switch)
2) I turned the rear fan up till the fake fan started to fairly fast.
3) I turned the side fan to 5v (blowing into the case). This caused the fake fan to slow down to a stop and turn slowly off and on.
4) I turned the side fan to 12v and the fake fan wouldn't turn.

Now I couldn't have done that test or even thought about it without the fan controller. I was kinda surprised that the side fan would actually cause the airflow disturbance, and found it worked better forcing air out, which was actually better on my 8800GTS.

So like I said before, just test it out for yourself to see what you can do to make things better.

Grimmy, I'm very much agree by the way you test your casing air flow...give peoples an idea how to understand the work of air flow inside their cases.

I would set the fan up to suck the air out ....always thought a negative air pressure was best for cooling the contents of a case , ie more fans sucking out than in , I avent even bothered puting a side fan on my 900 as it keeps my 8800gts OC nice and cool anyway with a standard setup.


just my tuppence