View Full Version : I detached cooling fan and forget which side faces out (see picture)

June 8th, 2012, 08:50 AM
I detached the cooling fan from the cooling tubes and I forgot which side faces out and which side faces toward the tubes. Is it A or B?
Please refer to the attached pictures.

June 8th, 2012, 09:07 AM
The fan may have an arrow marked on its casing showing the direction of flow. Otherwise, if in doubt connect it to the power and (briefly) switch the power on. You can use a sheet of paper to detect the flow if you aren't sure.

June 8th, 2012, 09:10 AM
Should air be flowing towards the processor or be flowing away?

June 8th, 2012, 09:56 AM
Should air be flowing towards the processor or be flowing away?
As long as it's moving as much air as possible across the heat sink it doesn't matter, although in practice away will generally be best for ATX style layouts. You want to ensure a smooth flow of cool air into the box, across the hot components, and then the hot air smoothly exhausted. In the standard ATX box that will mean fresh air coming in through the front of the box and out the back and/or side.

June 8th, 2012, 04:19 PM
I think it would be easier if you told us the make & model of the cooler.

June 8th, 2012, 07:46 PM
A - exhausting the air away from heatsink
B - intaking air into heatsink

"A" should be the correct way.

June 8th, 2012, 08:01 PM
Paqman, you're right. There was an arrow showing direction of flow.
Thank you, everyone, for your input.