I didnt know where to post this message so ill post it here please go here and look at the pic i drew of my case (yes i know im not a good artist) but just see whats u think is good.bad.ugly, ok thanks
Matt
go here
Matt
go here
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Case Fan Placement 1
- Thread starter pirate252
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1
- #3
I think your design is fundamentally flawed, although I am sure it will work fine.
You seem to have a front to back air flow in place which does not take into fact natural convection (hot air rises)
A better design would be to have lower intakes to upper exhausts. (in at the bottem, out at the top) Calculating a ballanced CFM, (same coming in as going out)
The other thing is air cooling! just because you put 12 fans in a case does not mean it will run much cooler than a case with 6, because the air reaching your components will be no cooler, so beyond a certain air flow the gains are relatively minor and don't forget your power supply will be generating extra heat powering all these fans.
Now if you could lower the temperature of the air going into the case in the first place this would seriously make a differance! Martin
Just trying to help, sometimes falling short, I am only human after all.
You seem to have a front to back air flow in place which does not take into fact natural convection (hot air rises)
A better design would be to have lower intakes to upper exhausts. (in at the bottem, out at the top) Calculating a ballanced CFM, (same coming in as going out)
The other thing is air cooling! just because you put 12 fans in a case does not mean it will run much cooler than a case with 6, because the air reaching your components will be no cooler, so beyond a certain air flow the gains are relatively minor and don't forget your power supply will be generating extra heat powering all these fans.
Now if you could lower the temperature of the air going into the case in the first place this would seriously make a differance! Martin
Just trying to help, sometimes falling short, I am only human after all.
HI all
Paparazi is spot on as far as Thermodynamics are concerned, and for this reason he get a star from me.
But what about Aerodynamics?!
I assume as a minimum you will put a mobo inside the case, then a HDD and a CD drive then you need to run ribbons from your drives to the mobo (Wireless technology for drives is not affordable yet). Therefore creating barriers for your airflow and because you are rushing the air in and out again there will be some parts inside the case that will be starved of cool air.
The other properties of fast airflow are boundary layer (the area of dead air between the surface of an object and the flowing air) and turbulence (partial vacuum). The faster the air flows the thicker the boundary layer. This layer will act as an insulator and will not allow any heat exchanges. Air come in fast flies over the boundary layer without cooling anything and then it is shoved out again.
The best solution is minimum fans and not the maximum. AMD suggests no intake fans and I quite agree with them. Air needs to gently travel around inside the case and come in contact with all components including diodes, resistors, capacitors etc to be able to take away their heat other wise local hot spots would be created.
I have deliberately avoided repeating what Paparazi has already posted.
I personally prefer using no intake fan, 2 exhaust fans (including PSU fan) and heat sinks rather than fans as much as I can for internal heat exchange eg on HDD, North Bridge and video chips This way will also not have the head ache of if HDD cooling fans packing up, taking the HDD out with it as well. In hot climates just add some ventilation holes on to for the trap heat to escape and add some more slots to the bottom for extra air to enter.
Lastly, Use metal legs connecting mobo (every connection possible) to the chassis, so using it as a heat exchanger for the mobo.
Paparazi is spot on as far as Thermodynamics are concerned, and for this reason he get a star from me.
But what about Aerodynamics?!
I assume as a minimum you will put a mobo inside the case, then a HDD and a CD drive then you need to run ribbons from your drives to the mobo (Wireless technology for drives is not affordable yet). Therefore creating barriers for your airflow and because you are rushing the air in and out again there will be some parts inside the case that will be starved of cool air.
The other properties of fast airflow are boundary layer (the area of dead air between the surface of an object and the flowing air) and turbulence (partial vacuum). The faster the air flows the thicker the boundary layer. This layer will act as an insulator and will not allow any heat exchanges. Air come in fast flies over the boundary layer without cooling anything and then it is shoved out again.
The best solution is minimum fans and not the maximum. AMD suggests no intake fans and I quite agree with them. Air needs to gently travel around inside the case and come in contact with all components including diodes, resistors, capacitors etc to be able to take away their heat other wise local hot spots would be created.
I have deliberately avoided repeating what Paparazi has already posted.
I personally prefer using no intake fan, 2 exhaust fans (including PSU fan) and heat sinks rather than fans as much as I can for internal heat exchange eg on HDD, North Bridge and video chips This way will also not have the head ache of if HDD cooling fans packing up, taking the HDD out with it as well. In hot climates just add some ventilation holes on to for the trap heat to escape and add some more slots to the bottom for extra air to enter.
Lastly, Use metal legs connecting mobo (every connection possible) to the chassis, so using it as a heat exchanger for the mobo.
Antimatter
IS-IT--Management
In my opinion, an 80mm intake fan at the lower front of the case can be invaluable.
The cases I prefer to use have a foam air-filter for getting rid of fan-killing dust, and require a fan to draw air through the filter(instead of through unfiltered holes in the case).
From what I've seen, 7200+ RPM HDDs require active cooling and the front case fan can be used to circulate air past the HDD.
In the event of video card fan failure, the front fan keeps air circulating over the video card heatsink, possibly preventing failure.
My preferred exhaust fan setup is dual fan PSU and a secondary low speed 60mm or 80mm exhaust fan.
The cases I prefer to use have a foam air-filter for getting rid of fan-killing dust, and require a fan to draw air through the filter(instead of through unfiltered holes in the case).
From what I've seen, 7200+ RPM HDDs require active cooling and the front case fan can be used to circulate air past the HDD.
In the event of video card fan failure, the front fan keeps air circulating over the video card heatsink, possibly preventing failure.
My preferred exhaust fan setup is dual fan PSU and a secondary low speed 60mm or 80mm exhaust fan.
- Thread starter
- #7
Thanks for all the input everyone, the reason for the fan near the pci slots was to get rid of the known dead spot right there, i guess that could be taken care of by the air flowing intoo the case from the front though...the hard drives are right in the way of those intake fans so that should slow down the air speed, and also there is a filter, so i dont think that it will make to much of a wind tunnel effect, but what u have all said will help me out alot, by the way the top blowhole is also a 80mm....i have also heard that its better to be puching more air out than in to take advantages of the negitive air pressure to suck air in though other holes, is this not true...thanks all!!
Matt
Matt
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