Cooling 'Corsair 400R'

[Mark SB]

Title mentions the case I have.
I have 3 Intake fans, two 120mm fans on the front and one 120mm fan fom the bottom. All three of them are connected to PSU due to its molex pin connection, so they run at 100 percent the entire time. I also have 3 exhaust fans, two 140mm at the top and one 120mm fan at the rear. These can be controlled via fan control. I want to know:
- Is this safe?
- At what speeds should my exhaust fans be since intakes are all at 100.
- Positive or negative air pressure.

Thanks in advance .

 

[Darkbreeze]

Are you using a fan hub to control the exhaust fans or are they connected to the motherboard?

What is your motherboard model number?

Positive pressure, WAY positive, except when the exhaust fans are at high speed.

 

[BottleGamer]

Yeah its safe
There is not really a clear decision between positive and negative airpressure
Just make sure that you dont have fans that pull in a lot of air but barely anything that exhausts
And every Case has its own airflow so play around with your fan settings and see when you are getting the best results for your own setup

 

[Darkbreeze]

Yeah it's safe
There is not really a clear decision between positive and negative airpressure

How could there not be a decision between positive and negative pressure when you have three thermally controlled exhaust fans that spin at a low RPM until the system is under a high load, and three intake fans spinning at max RPM at all times? That's positive pressure in any aerodynamic study I've ever seen.

As far as it being safe, that would depend on a lot of factors like the PSU model, WHERE the exact fans are pulling power and being controlled from and whether there are any splitters or cheap hubs being used. I've seen plenty of integrated fan hubs completely melt the entire wiring assemblies in units where multiple fans were being used in excess of what was intended.

 

[BottleGamer]

How could there not be a decision between positive and negative pressure when you have three thermally controlled exhaust fans that spin at a low RPM until the system is under a high load, and three intake fans spinning at max RPM at all times? That's positive pressure in any thermodynamic airflow study I've ever seen.

He didnt say that they are thermally controlled
And what i meant is that if you look at the poll here http://www.tomshardware.co.uk/forum/238184-31-case-airflow-positive-negative-pressure you can see that there is apparantly no such thing as "positive air pressure is the best" or the other way arround

 

[Mark SB]

@darkbreeze: Input fans are connected to PSU ( 'Corsair 750W') and exhaust fans to a fan hub that I can manually control. One exhaust fan is directly connected to Mobo, but it is a 3 pin, hence that is also always at 100. There are filters for both intakes.
I have an Asus H-97 Pro Mobo.

So actually, I control the speeds of 2 exhaust fans. Should I connect one Intake fan to the fan hub to prevent all 3 intakes blowing in too much air?

 

[BottleGamer]

@darkbreeze: Input fans are connected to PSU ( 'Corsair 750W') and exhaust fans to a fan hub that I can manually control. One exhaust fan is directly connected to Mobo, but it is a 3 pin, hence that is also always at 100. There are filters for both intakes.
I have an Asus H-97 Pro Mobo.

So actually, I control the speeds of 2 exhaust fans. Should I connect one Intake fan to the fan hub to prevent all 3 intakes blowing in too much air?

You can
I myself would try connecting it to the fan hub, set the speeds and just see how the temps are going from your gpu and your cpu because i dont think there is an optimal pre-setting for all cases and setups so just try everything and keep the option where your temps are the best
But even if you have more intake or more exhaust it wont affect the stability of your system

 

[Darkbreeze]

Just because a fan is connected to a 3 pin fan does NOT mean it is an uncontrolled 100% "on" configuration. There are few "system" fans that are 100% on. Most are 3 pin voltage controlled through the BIOS and are thermally regulated. 4 pin PWM motherboard connections are preferred, but 3 pin voltage controlled headers are just fine and in most cases are not the "sys" type, but are the "cha" or chassis type.

Personally, I rarely recommend using the integrated fan controllers that come with cases. They are usually low quality affairs with a tendency to overdraw current and fry things. The specs for your motherboard list one 4 pin CPU fan header and three 4 pin chassis fan headers. That means six case fans plus the CPU cooler could be controlled via your motherboard using three of these for the case fans which work equally well using 3 or 4 pin fan models as the fourth pin is only for the PWM signal and is not essential when using 3 pin voltage controlled fans.

http://www.newegg.com/Product/Product.aspx?Item=N82E16812162026


Two fans per header is well within tolerance. Three fans per header can work, but it's not recommended as you move dangerously close to overloading the circuit design by doing so. Two per header won't even come close to the amperage limit. This would allow all your case fans to be voltage or PWM controlled through the motherboard BIOS, and most your fans should be compatible. There are likely standard 3 or 4 pin to Molex adapters being employed in order to connect to the power supply and if so they can be removed in order to use the standard fan connectors that are directly integrated with the fan cabling.

This would make your system far more efficient, no need to manually adjust fan speeds, use far less power saving money as they won't be running at high speeds unless demanded by the current load. The system will be far quieter the majority of the time and you will have a system that is close to a neutral air pressure with them all being controlled thermally, neither positive nor negative, which is a good balance of performance and dust suppression. Dust suppression is the only real advantage of a positive pressure configuration.