What is forced air pc cooling?

[medbor]

The cpu fan operation is normal for a case temp of 50 c. My phenom x4 9550 has a STOCK max case temp of 61 c. While you have a phenom II I am reasonably sure the tech hasen't changed much it should be at the same max case temp or maybe 62, 63 c.

 

If you are looking to quiet the stock heatsink reach a case temp below 40 c.

 

That case has those three fans included. The case temp is 50 c. It is high for the amd cpu, but still allowable.

 

My analysis of the case cooling would be a poor grade. The front fan has a drive bay directly in front of it impeding air flow. The grille area and mesh spacing for the 120mm front fan is unknown to me but it appears more asthetic than functional. Low speed fans for a high end computer is pretty silly, but I have no idea what the fan cfm is.

 

If that were my case and in consideration of the 50 c case temp I would be measuring the front grille area and the mesh spacing. Taking off the fans and reading the fan specs on the fan sticker. Putting the fan model number into an internet search engine to determine what cfm and rpm the fans are rated at. I would remove the drive bay in front of the front fan; however, it may not be getting enough air through the front bezel.

 

To determine what fan performs better than a current fan installed. The manufacturer fan rpm/cfm data need to be compared. For example the installed 120 mm fan is rated at 60 cfm and the fan intended for upgrade is rated at 70 cfm then because the greater cfm indicates more air flow it is better. I would use the fan law cfm2 = (rpm2/rpm1) x cfm1 when the fan will be operating at different rpms, for example when the fan will be speed controlled for quiet operation or light pc use. The fan law numbers the fan operation 1 and 2 which represent 1 for the manufacturer tested state and 2 for the speed controlled state. Now the installed 120 mm fan is rated at 60 cfm and 1500 rpm, but is speed controlled to 1100 rpm then by the fan law (1100/1500) x 60 is 44 cfm air flow at the speed controlled state. The fan intended for upgrade is rated at 70 cfm and 2000 rpm and will be speed controlled to 1100 rpm then by the fan law (1100/2000) x 70 is 38.5 cfm air flow at the speed controlled state. Therefore, the installed fan will provide greater air flow than the upgrade option.

 

I would consider a fan grille mod of the round wire type. This type of grille allows the most air flow through it.

 

While the display on the chassis monitors temps with the included sensors it is important to place them in the optimal position. Double check the temps in bios, or software.

After the case displays 50 c restart the os and enter bios and go to the pc health screen to read the component temps.

My gigabyte mobo came with an oc utility which has a health monitor screen to display temps perhaps asus has a simular utility which will display temps, or find a different utility which will display the temps.

CFM is far from linear with respect to RPM. It is exponential.

[red1776]

I disagree with the 'passive ' aspect of your definition. I use a negative airflow setup (just over 1000CFM total , 450 CFM in...and 550 CFM out) and have more fans pulling air out than pushing air in to the case, but both exhaust and intake are active.

Typically a negative pressure setup will run a little cooler, but attract more dust.

[sticknstone]

CFM is far from linear with respect to RPM. It is exponential.

 

medbor the whole post was quoted and I am unsure what the reply is related too. sorry.

[sticknstone]

I disagree with the 'passive ' aspect of your definition.

 

 

What is the disagreement?

[Nyt]

This is my setup: Total of 1150CFM

Exhaust as negative :

100

110

110

90

90

90

=590CFM exhaust

 

Intake as positive :

90

90

90

90

90

110

560CFM intake

 

And my temps are good . There always needs to be a balance between in and out . Usually more exhausting should occur .

[VaporX]

 

And my temps are good . There always needs to be a balance between in and out . Usually more exhausting should occur .

 

I have no doubt your temps are good, but then again most modern PCs reach a cooling platuea at a much lower fan number. While common sense would indicate that balanced is best when you look at the physics of it that is not the case. Again I will reference people to a look at fluid dynamics, the best way to study this scenario. Balanced or negative flow systems allow the creation of eddys of air that create hot spots. By over pressuring the case, positive air flow, you force the air to find all the exits it can and high pressure of the cooler outside intake forces the hot air to move.

 

While I have yet to see a case truly done right by these models the Raven series is close. The idea is that using large air intake and then a pure chimney exhaust system you SHOULD achieve the best overall air cooling scneario. The principle is that you will force hot air to have to find an exit due to positive air pressure. The only exit easily provided is the top of the case with lets say dual 120mm fans. The air would be naturally inclined to do this anyway due to the warmer air rising from the cooler intakes. The result is an acceleration of the natural prcoess and thus a much higher warm air evacuation rate than the fan ratings would suggest.

 

I did some testing of this during a review of the Armor A60 case. We reversed the rear fan to intake and put in a bttom fan as well. We put a second 120 on the top for exhaust, blowing out over a 120mm radiation (coolit ECO). The result was an amlst 5C drop over the stock configuration in overall internal system temp.

 

Seems I even saw a video someplace of one of the cases using some of this design idea showing that even without fans the case moved air pretty well through natural heat rise exhaust.

[krazypoloc]

I have no doubt your temps are good, but then again most modern PCs reach a cooling platuea at a much lower fan number. While common sense would indicate that balanced is best when you look at the physics of it that is not the case. Again I will reference people to a look at fluid dynamics, the best way to study this scenario. Balanced or negative flow systems allow the creation of eddys of air that create hot spots. By over pressuring the case, positive air flow, you force the air to find all the exits it can and high pressure of the cooler outside intake forces the hot air to move.

 

While I have yet to see a case truly done right by these models the Raven series is close. The idea is that using large air intake and then a pure chimney exhaust system you SHOULD achieve the best overall air cooling scneario. The principle is that you will force hot air to have to find an exit due to positive air pressure. The only exit easily provided is the top of the case with lets say dual 120mm fans. The air would be naturally inclined to do this anyway due to the warmer air rising from the cooler intakes. The result is an acceleration of the natural prcoess and thus a much higher warm air evacuation rate than the fan ratings would suggest.

 

I did some testing of this during a review of the Armor A60 case. We reversed the rear fan to intake and put in a bttom fan as well. We put a second 120 on the top for exhaust, blowing out over a 120mm radiation (coolit ECO). The result was an amlst 5C drop over the stock configuration in overall internal system temp.

 

Seems I even saw a video someplace of one of the cases using some of this design idea showing that even without fans the case moved air pretty well through natural heat rise exhaust.

I agree....