I'm confused over how proper airflow is suppose to work in a case. Lots of cases these days have the power supply at the bottom of the case and sli isn't uncommon. Just about every case has 1 or 2 fans on the bottom front for intake and 1 or 2 in the top back to eject the air. Am I wrong in thinking that just about all the cool air is going to be immediately sucked out through the PSU and video cards? How is the air suppose to take a 90 degree turn upwards right after the fans, around the video cards, and then into the cpu heatsink. I think it would make much more sense to just have a third fan in the front that blows directly onto the processor. Would this not greatly increase cooling performance? I know 3 fans would take up a lot of space, but on full towers, that can still leave 3 open drive bays. I can't for the life of me find a decent case that does this. I tried the x500 because that has exactly what I'm looking for, but I can't comfortably fit 3 hard drives and my bottom video card is almost scraping the bottom of the case, getting no airflow. Any advice/info would be awesome.
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Proper Airflow. Am I confused?
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CapnCrunch53
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This is actually precisely the problem I have in my case; I have difficulty getting airflow to my cpu cooler. Especially in mid-size towers with multiple video cards, it can be a bit of a challenge. However, both the Antec 900 and 1200 combat this by having multiple fans fairly high on the front panel; these cases are the best examples I could think of but there are others as well.
EndersShadow
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I went with a Coolermaster ATCS 840. It has 2 240mm fans at the top that normally blow air out. I turned one into a intake and it pulls air straight into the CPU heatsink. The other top mounted fan sucks air out as does a fan located at the back of the case. By doing this the CPU has a dedicated air supply seperate from the intakes used for the PSU, GPU and HDD's.
The PSU is bottom mounted and takes in air from underneath and the GPU has a 240mm intake which is also supplemented by three additional 120 mm fans. Running at full speed (via a fan controller) the only noise that is audible is the GPU fan which I have running at 40 percent at all times. Is a very quiet setup and runs with really good temps.
The PSU is bottom mounted and takes in air from underneath and the GPU has a 240mm intake which is also supplemented by three additional 120 mm fans. Running at full speed (via a fan controller) the only noise that is audible is the GPU fan which I have running at 40 percent at all times. Is a very quiet setup and runs with really good temps.
I'm going back and re-contemplating the PC-P50 Armorsuit thinking it now has the best cooling with almost all the features I want. (no mobo tray). I can get an extra 120mm mount for the front, and could do what you mentioned and turn one of the top fans upside down.
Would all this be better airflow than the PC-A70 with an extra 120mm in the drive bays?
Would all this be better airflow than the PC-A70 with an extra 120mm in the drive bays?
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I've got a Coolermaster 590 and the PSU draws air in from under the case (there's a good 1/4" between the desk and the case bottom). But even if I inverted the PSU, the fan in it doesn't really draw that much air. The main purpose for the front fans is to draw cool air into the case and the other fans will pull what they need.
nobody_here
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ive built lots of systems and modded lots of cases, and i can tell you cutting a "blowhole" in the top and mounting a 120mm fan in it to draw the air up and out made the biggest difference in my setups over the years
That's very helpful, thank you.
Has anyone else done what EndersShadow has? The PC-P50 has two 140mm fans on top and I could invert the back one to blow air right onto the cpu heatsink. The only bad part is that it might just suck in all the hot air that just got exhausted from the other 140. I'll try both ways when I get the case and see what the difference is. I'll also install another 120mm fan in the middle-front of the case that will blow directly on the video cards. I'll only have 3 hard drives anyways. Without it, most air would just have to be pulled from the front grills because the single 120mm intake will be completely blocked by hard drives. I have a scythe mugen 2 I'll be using that I can put 2 fans on, so a total of 3 including the rear 120mm will be jetting air across the heatsink.
With cases that have fans on the top, is there ever a problem of it sucking air away from the cpu?
Scythe's Kaze Maru fans are 140mm...
EndersShadow
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I would take the 140mm fan closest to the front and invert that one, not the one at the back. That way you basically have a U of airflow. You have one intake bringing air down straight toward the CPU heatsink fan. The CPU heatsink fans pushes it through the heatsink and out the back where it is either exhausted either straight out the back with one of the 120mm fans or straight up via the other 140mm fan.
Here is an example of the airflow in my case. Please note all the fans were not added at this time as this was during my initial build. I also opted for a fan controller to allow me to modify the airflow in and out to keep noise at a respectable levels. The fan controller I purchased can be set to manually adjust the fan rpm's based on temp probes. This works quite well as my case is almost entirely silent, minus the insanely loud GPU fan which is also set to a manual rpm level via RivaTuner.
Also just something to consider. The Case you are looking at (PC-P50) does not have solid 5 1/4 bay covers. This may seem like a good idea to increase airflow, however after I bought my Thermaltake Armour+, I got rid of it for that reason. This is because any noise in the case is pretty audible and can be heard from a decent distance away. If you do get this case make sure the fans you purchase are low dba fans otherwise you risk hearing them outside the case and depending on your noise preference can get quite annoying.
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Good point OP.
I have a Lian Li Tyr PC-X500 where the PSU is NOT in the bottom. This means that the the second front intake (undervolted Scythe's Kaze Maru 140mm actually) is directly aligned with the CPU which is directly aligned with the rear exhaust.
The result? I am able to run my CPU cooler passive. No fan on the heatsink at all, just ducting to focus the existing airflow. And this is on an overclocked i7 with a GTX285. Of course, people are skeptical of this, but that's an advantage of well designed air flow. http://i159.photobucket.com/albums/t128/echn111/IMGP0117.jpg
But if you're like most people, and prefer to get a case that interferes with airflow, just put a fan on the CPU heatsink and turn up the case fan speeds and you're fine. It is your choice after all.
I have a Lian Li Tyr PC-X500 where the PSU is NOT in the bottom. This means that the the second front intake (undervolted Scythe's Kaze Maru 140mm actually) is directly aligned with the CPU which is directly aligned with the rear exhaust.
The result? I am able to run my CPU cooler passive. No fan on the heatsink at all, just ducting to focus the existing airflow. And this is on an overclocked i7 with a GTX285. Of course, people are skeptical of this, but that's an advantage of well designed air flow. http://i159.photobucket.com/albums/t128/echn111/IMGP0117.jpg
But if you're like most people, and prefer to get a case that interferes with airflow, just put a fan on the CPU heatsink and turn up the case fan speeds and you're fine. It is your choice after all.
I have 1200rpm scythe slipstreams I'll be putting in the case. I'll also be putting an extra one in the middle open area in the front of the case so there's 2 intake plus possibly one on the top. I tried these fans for a minute or two in a different case and they were whispers quiet compared to the fans I've been using. I'm hoping the sound will not be a problem.
just so you know, each additional fan creates more noise. i.e. three 20db fans make approximately 26db of noise.
from: http://www.vent-axia.com/knowledge/handbook/section2/noise.asp
Everything is in my profile and a full link is here. It's a Gigabyte GA-EX58-UD5, and the CPU is running at mild 3.6GHz. Yes there is room for a fan, but why bother? Less fans mean less noise. And without a CPU fan, and the case fans running at around 800rpm, the mild overclock has passed a 5 day 24/7 non-stop run of Prime95 (+ continuous torrent up/downloading + occational internet browsing) on all 8 cores and passed. Temps are meaningless compared to proven stability via a stress run like that.
If it lowers ambient temperature around CPU or heatsink can benefit from additional airflow...
(like passive heatsink needing that ducting to keep air moving through it)
Except in extreme PCs modern high efficiency PSUs don't need that much air when they're on bottom and don't have to suck in air heated by CPU, mobo etc.
As for P50... it's rather cramped for high end PC. Just one or two HDDs more would make lot of cable spaghetti.
http://www.overclockersonline.net/images/articles/lianli/pcp50/large/ll35.jpg