Cooling Diagram

I just wanted everyone's opinions of my cooling diagram for my new system I will be building soon. I drew a little diagram explaining it.



With the exception of the PSU fan, which is 80mm, all fans will be 120mm aluminum fans (for excellent CFM/noise ratio). This will include a 120mm aluminum fan over the SLK900A (I'll achieve this by using a fan adapter, which should also eliminate the deadspot).

The big grey thing is the center in the CPU ducted to the rear 120mm (intake).

Is this a pretty good air cooling setup? Will the single 120mm blowhole be enough exhaust? Also, is it safe to replace the PSU fan with an aluminum one?

the 120mm back one should be exaust

Make sure you seperate back intake and PSU exhaust so that you don't get recirculation of hot PSU exhaust into your CPU duct.

Or, you can have the side panel intake over the CPU w/ duct and make the back exhaust...

Looks like a low noise wind tunnel!

Does your power supply have a second fan [underside intake right above CPU normally]?

No, my powersupply only has the single exhaust fan on it. I will be replacing the stock fan with an 80mm aluminum fan and possibly adding a fan to the back/bottom of the PSU if I have the space.

What would be the most effective way of making sure the back intake isn't sucking in the PSU exhaust (without adding some strange exterior ducting, going for aesthetics here too).

Without adding external ducting, there is no way.

The following is assuming you are making the holes yourself. If the holes are precut in your case and you're not changing them, some of my advice will not be applicable.

The way the airflow is set up, you'll have three 120mm fans blowing in, one 120mm fan blowing out, and one 80mm fan blowing out. Assuming all the 120mm fans blow the same amount, and the 80mm fan blows about half the amount, you'll be left in a very positive pressure situation. Usually I take the average airflow in and out to calculate total airflow, so in this case you'll be pushing about 2 and a half times a 120mm fan's worth of air no matter how you set up the fans (though this is only an estimate: there are logical curves to this).

What you need to do is orient your fannage to create the best airflow pattern. By the relative sizes on your diagram, I can assume this is a large (full tower?) case, yes? Your front intake fan is in a good place. The side intake fan should be higher - covering your AGP slot, northbridge, and CPU heatsink. The rear 120mm fan should be exhaust to prevent recycling hot PSU air. Since you'll have the side intake over the CPU, you don't want the duct to the rear anymore. You can duct the side fan directly to the CPU (neglecting the NB and AGP), or you can leave it free. With the 120mm fan on the heatsink inside the case, you wouldn't have much room for a duct anyway. The top blowhole is a good idea, but if you're worried about negative pressure and dust problems, you could get a slower, quieter fan. The blowhole doesn't need to be much more powerful than 30 CFM in most cases; it doesn't need to forcefully pull air over a component off of a heatsink; hot air is literally trying to get out there anyway.

In general, you want the air to move in a fairly uniform direction throughout the case. This is acheived by having all the intakes in the front of the case, and the exhausts in the rear. The side intake can screw it up three-dimensionally, but not nearly as much as an intake on the rear panel can.

Here is my "corrected" version of your diagram for your consideration:

I like your original Idea however you may need to find a remedy for the PSU exaust being right ablove the intake, Restorer's is also good but I might put an intake over the video card as well, or have 2 more powerful intakes and weaker out's and leave the slot on the back under the video card open so that air can get out after it goes over/through the videocard heatsink(s).

With restorer's i would worry about pci / agp cooling. My old geforce 3 got really hot before i put 2 fans over it. Personally i would use Sandrock's plan but get rid of the duct and reverse the back fan so it blows out.

ahh i remember my 1st "cooling diagram"... the memories....

i think restorer's idea is the one to go with... that is if thats how the real-life model would work...

Thanks for all the insightful replies!

My original idea was to place a 120mm over the PCI/AGP slots and another directly over the CPU which could then be ducted to the CPU. I decided this would take up alot of space on my side panel and I also wanted to cut a window into it. The two 120's would take up most of the window, and you would hardly be able to see anything!

How about this?

Can I turn the PSU fan backwards, drawing in cool air, mount another 80mm fan on the back of the PSU which will blow the hot air directly into the path of the 120mm blowhole? Maybe I can even stick a TT ducting mod pushing the PSU airflow directly at the 120mm blowhole. Discuss.

-Edit added diagram
-Edit2 - To remedy pressure differences, I'll 7v the intakes, leave exhaust at 12v, should even pressure a tad?

i think that would heat up the inside of your case.

Definitely don't turn the PSU fan around. The will fill your case with hot air, even if it would seem to exhaust into the path of the 120mm blowhole. Because there is only one fan on your PSU,and it's on the wrong side, the path the air will actually follow is unpredictable and could push hot air into your CPU area or elsewhere.

I think the PSU intake would be too much air going in to funciton well.
It may also make it heat up like they said, but I think due to how close it is to the outlet it wouldnt matter much.

Somthing you could do is flip your PSU over and make a blowhole over it, if it has a fan on the bottom you can just flip it over and have it blow out of hte case and then the one on the back blow in...

like this:

that would be good, except the intake at the bottom might not function well, unless his case is raised. and i would make the front fan intake.

my $0.02

koontz946 said:

that would be good, except the intake at the bottom might not function well, unless his case is raised...

...my $0.02

Click to expand...

why is that?

I feel ignored ....read my second post...isn't that what Restorer said just w/ nice diagram??? Yet everyone likes Restorer's idea....???

If you turn your PSU fan around, make sure your PSU's "new exhaust" is right next to your top blow hole so that your don't blow in hot air into the case. But I'd much rather leave the PSU fan alone and put intake over your CPU on the side panel and keep the back fan as exhaust.

As far as bottom panel intake goes, you want to have enough space between your floor/desk and your case so that the fan will actually have some air to blow in.

Now, I'm gonna go work on my diagram skills

threeputt said:

I feel ignored ....read my second post...isn't that what Restorer said just w/ nice diagram??? Yet everyone likes Restorer's idea....???

If you turn your PSU fan around, make sure your PSU's "new exhaust" is right next to your top blow hole so that your don't blow in hot air into the case. But I'd much rather leave the PSU fan alone and put intake over your CPU on the side panel and keep the back fan as exhaust.

As far as bottom panel intake goes, you want to have enough space between your floor/desk and your case so that the fan will actually have some air to blow in.

Now, I'm gonna go work on my diagram skills

Click to expand...

Having teh 1337 paint skillz helps you get recognized in these threads... lol I think most fo these are good ideas, and yours are god too.

The case is only a midtower, but its a little bigger than most midtowers (I think). I took a few pics of the case so you'll have a better idea of what im working with.