Quite confused when desgining a ventilation strategy - anyone mind giving some thoughts or comments

[finix429]

Hi, I'm going to build my first desktop (for gaming and programming) and think about the cooling system for my desktop. I'm planning to use the Corsair 350D Window as my PC case, and LEPA AquaChanger 240 as my CPU cooler. These can be changed depending on the response in this thread. I'm currently thinking of a good ventilation strategy would be better for Corsair 350D Window. I've known the pros and cons of positive and negative air pressure.

If I create a negative air pressure (front intake with dust filter, rear exhaust, and top exhaust), the advantage of the LEPA AquaChanger 240's fan is not used. I guess the fans are supposed to be used as intake since it boosts down-force air pressure and crease high-volume airflow. Beside, based on the example layout inside the Corsair 350D Window, most cool air will probably go from the video card and power supply to the CPU. Is this true in a negative air pressure setting? If so, will this hurts my CPU given a liquid cooler used?

If I create a positive air pressure (top changed to instake), then the hot air from rear will probably go back from the top (also, dust will be introduced due to no filter). Although there is a radiator for the top fan, but I doubt its usefulness given a long time running of my computer. Also, considering the airflow direction (air coming from the top and front), airflow direction will probably be messed up in the rear-bottom. There will certainly air going out from the bottom of the case, but I wonder if the messed-up airflow hurts the video card and power supply in the rear-back.

Any comments and ideas will be appreciated

Thank you,
Finix

 

[timeconsumer]

Have you considered mounting the radiator to the front of the case as an intake?

But FWIW, I don't think either setup will make a huge difference. I would try it as both intake and exhaust and see how it affects temperatures.

 

[dudeman509]

Don't intake in through the top of the case - exhaust out through the top and back of the case. Intake fans down low in front (or bottom, if you can).

Go for negative pressure.

 

[finix429]

Have you considered mounting the radiator to the front of the case as an intake?

But FWIW, I don't think either setup will make a huge difference. I would try it as both intake and exhaust and see how it affects temperatures.

Thank you for your thoughts.

Yes, I have thought about using it as front intake. However, the fan speed is not static, I suppose it may vary depending on the temperature of CPU. I would prefer to using a static speed fan to make the intake air flow steady.

I'm just thinking of changing a CPU-cooler. The boosted down-force air pressure provided by the LEPA AquaChanger 240 seems unnecessary for me. Maybe Corsair H100i would be better.

 

[finix429]

Don't intake in through the top of the case - exhaust out through the top and back of the case. Intake fans down low in front (or bottom, if you can).

Go for negative pressure.

Yeah, I'm thinking negative pressure might be better. Cause negative pressure seems provides more cooling than positive pressure. Thank you for your advice.

 

[Saberus]

There is a third strategy that is used in rack-mount servers: Neutral pressure, or balanced airflow. Give yourself equal levels of intake and exhaust, and you get some of the benefits of both. You get the efficient scavenging of a negative pressure system and the lesser dust and ease of intake filtration of a positive pressure system.

 

[finix429]

There is a third strategy that is used in rack-mount servers: Neutral pressure, or balanced airflow. Give yourself equal levels of intake and exhaust, and you get some of the benefits of both. You get the efficient scavenging of a negative pressure system and the lesser dust and ease of intake filtration of a positive pressure system.

That sounds cool, but I find many people do not suggest neutral pressure cause the air will stuck in the case. I guess the one you mentioned might be achieved by some other techniques. I would just go for a simple solution since I don't have any experience building a desktop before (I always think simple techniques are steady). Thank you for this info

 

[Saberus]

There is a chance for pockets of heat to simply circulate of there's obstructions or low amount of airflow, so it really drives home the need to be tidy with your cabling, and having enough fans on both ends to keep the internal air from sitting for too long. But more fans leads to more noise, rackmount servers with very high flow are loud. But they are made that way because they have to be able to run hard 24/7/365. For a home PC, you can use larger fans which are quieter, and mount them with vibration isolation (rubber grommets) to further reduce noise. Good fans aren't expensive compared to other parts, and with a home system, there's no such thing as too cold really.

 

[finix429]

There is a chance for pockets of heat to simply circulate of there's obstructions or low amount of airflow, so it really drives home the need to be tidy with your cabling, and having enough fans on both ends to keep the internal air from sitting for too long. But more fans leads to more noise, rackmount servers with very high flow are loud. But they are made that way because they have to be able to run hard 24/7/365. For a home PC, you can use larger fans which are quieter, and mount them with vibration isolation (rubber grommets) to further reduce noise. Good fans aren't expensive compared to other parts, and with a home system, there's no such thing as too cold really.

Thank you for those tips They are quite helpful. Regarding the air-flow-rate, should I increase the differences between in-flow and out-flow? or decrease? (That is, larger air pressure or small air pressure, which one is better?)

 

[Saberus]

I try to tend just slightly more out than in, but as close to equal as I can. Pressure's not as important as flow in the case, save high static pressure fans for the radiator, that's where it's most beneficial, to force air through the tightly packed fins.

 

[finix429]

I try to tend just slightly more out than in, but as close to equal as I can. Pressure's not as important as flow in the case, save high static pressure fans for the radiator, that's where it's most beneficial, to force air through the tightly packed fins.

I see. So, pick large fan for the front instake to increase the air-flow, and small fan for the rear and top exhaust to increase pressure which help exhaust out of case! Thank you, these advice are really helpful