shut your blow hole.

[zDmn]

i keep hearing people say that blow hole fans are counter-productive but nobody ever explains why. my friend thinks he is so badass for taking a dremel and cutting a fan hole in the top of his case but when i told him i heard that is a bad thing, he got all pisst off. but then i couldnt explain why. plz help!

 

[OulOat]

Blowholes disrupts the air flow inside of the case. Instead of air flowing from front to back, air is being siphoned through the top of the case. Whether it's bad or not depends on the case and air flow. If the case has a weak stream of air or the psu isn't on the top of the case, then a blowhole would probably help get rid of the rising warm air. However, if your case has a strong flow of air and the psu is at the top of the case, it would probably be best to leave the blowhole out. A case with good circulation should have it's most of its air volume replaced every couple mins, so not much warm air is being trapped in the top of the case. Plus, you will have the blowhole fan fighting with the psu fan for air.

Either way, leave your friend alone with his blowhole. If he feels happy and confident that it improves his temps, let him. Just laugh internally at him for installing more noise.

 

[amcdonald]

The whole straight line from front low to back high thing sorta gets screwed up when the air passes anywhere near my alpha8045/smartfan2...
in my experience I just open vents to direct what gets cold air first...

I just have a little lanboy and my psu and 1 antec blue (34cfm) far overpowered my front panaflo L1a intake. I had to open up vents otherwise the panaflo was being forced to spin faster than it wanted to because of the vacuum. (noisy) So I just took it out along with the mount, opened up the 4 empty pci slot covers, and I'm getting the same cpu temps and case dropped 2ºC... Smoke shows how much better the airflow is around the agpcard... and the vacuum is still pulling in substantial air from the front vents over the hard drive.
As for installing top blowholes... more exposed fans=more exposed noise/places noise can escape your case