Why do fans blow cold air

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mr_drehmomentdr.evil

"What is better? Blow cold air on it, or blow warm air away "

Hello,
I would say: it depends on how the CPU fan blows.
If the CPU fan blows the air onto the CPU cooler, then it would be better if air is blown from the outside onto the CPU fan.
But if the CPU fan sucks the air away from the CPU cooler, then it would be better if a suction fan was in the direct vicinity (e.g. with the Enermax power supply unit).
In my computer it is like this:
Alpha cooler with "sucking" fan - in the direct vicinity, the warm air is sucked off by the Enermax power supply unit and an 80mm case fan.

Describe what kind of case you have, which power supply unit with how many fans and where are they located, does the power supply unit suck air out of the computer or does it blow air into the computer?
Do you already have any case fans in there?

Mrs. Softwaremr_drehmoment

"Hello, I would say: it depends on how the CPU fan blows. If the the ... "

CPU fan: blow on (try to extinguish a candle by sucking in air), case fan: blow out.

mr_drehmomentMrs. Software

"CPU fan: blow it, try to extinguish a candle by sucking in air ..."

Hello,
First of all, when you blow out a candle, it has nothing to do with temperature, but only with mechanics - the flame is separated from the wick by the air flow and goes out due to a lack of fuel.

When the CPU is blown, the heat is distributed throughout the case - like the haze and smell in a kitchen without an extractor fan.

But if you suck off the heat from the CPU and let it be discharged into the open by fans, it's like in a kitchen with an extractor hood with an exhaust air duct to the outside - the booth is not polluted and there is no such thing as the thick air.
If you also have a thick fan that blows air into the computer through an air filter, you won't have any problems with dust - as Al Bundy says.

HeinBlöddr.evil

"What is better? Blow cold air on it, or blow warm air away "

Shovel away warm air !!!! Whether the processor fan blows on the processor or away from it, the effect is the same: heat is generated at the point! No matter how good the air throughput in the computer, it is more beneficial if the warm air is "disposed of" on the spot! Had the same problem, first blew in and then turned the additional fan. Result according to MBM: Blowing out lowers the temperature by 5 degrees compared to sucking in!

Al_Bundydr.evil

"What is better? Blow cold air on it, or blow warm air away "

The sucking out is relative and there are circumstances that I didn't take into account in the past. So the following:

A process that is blown is always a little cooler than one that is vacuumed, because the bottom cooling plate is blown directly, which is not the case with suction. makes about 3 to 5 Kelvin difference. (i.e. degree)

Furthermore, refer to suction or blowing into the housing. Actually, it doesn't really matter here if there are sufficient opportunities for warm air to escape when blowing in. The problem is, if you suck in air, you suck it through the floppy, through ventilated burners, etc.! This means that these devices get dirty much faster. In addition, in the case of relatively airtight housings, the effect of the power supply fan is also reduced, because the suction is contraindicated.

So contrary to my own earlier opinion> blowing in instead of sucking.

Your Al

gaga7dr.evil

"What is better? Blow cold air on it, or blow warm air away "

the whole thing depends on the cooler + board + power supply + case config, I claim that you can't say that across the board

what I can say, however, is the following:
the difference whether it blows on the CPU or sucks the air is prohibitive, but:
when he blows on it, depending on the constellation, he blows the hot air on the mainboard, RAM, graphics card, etc.
For this reason I decided to move the air away from the processor and to convey the hot air directly into the open air by means of 80s + a small duct (at the end of the duct there is still a 92s fan ...), so that's the story for me has become much cooler (not only CPU, but also board, RAM and graphics card, furthermore I suck in a bit of fresh air, among other things, this prevents heat build-up for me ... (and that's not without it ... )
hih
until then
PS: sorry, lack of time, I haven't read all the post's ...

Dr. Hookdr.evil

"What is better? Blow cold air on it, or blow warm air away "

Hi,
views seem divided. I say: BLOW ON IN ALL CIRCUMSTANCES !! I spare you and myself from having to scientifically substantiate this. But it is so!

Kind regards

Dr. Hook

The great Gurudr.evil

"What is better? Blow cold air on it, or blow warm air away "

Blowing away only makes sense if the air is directed outwards by the fan (duct to the housing wall on which a fan blowing outwards is still mounted). Then it works great.
Otherwise, blowing on the processor is the better alternative.

gaga7dr.evil

"What is better? Blow cold air on it, or blow warm air away "

sorry, but again:

*******************************************
the whole thing depends on the cooler + board + power supply + case config, you can't, I claim, say so across the board
*******************************************

cu
PS: don't want to turn on anyone stupid, just express that everyone is / can be right ...

mr_drehmomentdr.evil

"What is better? Blow cold air on it, or blow warm air away "

Well
I can't spare myself a big grin here.
Apparently there are two competing clans here:
The "suckers" on one side and the "blowers" on the other.
Well what the heck, I think "sucking" is much nicer. ;-))))

Anne Radtkedr.evil

"What is better? Blow cold air on it, or blow warm air away "

The fans we use and install in the computer store are all designed to suck in the air. This is also stated in the fan assembly instructions and directional arrows are attached to the fans themselves. Something more fundamental: Since the warm air is known to be at the top of the case, it is absolute nonsense to install a fan at the front at the bottom and a slot bracket fan at the bottom at the bottom. This is covered by the PCI cards anyway and the air is only blown out in the area of ​​the bottom 10 cm from front to back and has ZERO influence on the cooling in the housing, you can see this very well by blowing smoke from a cigarette into the housing! It is then better to fumble around a slot bracket fan and screw it on at the level of the processor at the rear left of the case where the many holes are already there. I myself put a 3-pack 40 mm fan under the burner, with the success of constantly 40 degrees on the processor plus / minus what is displayed incorrectly * grin * My theory: There is very little warm air at all and only from the power supply -Fan is removed, you just have to press in more from the front * g *

gaga7Anne Radtke

"The fans used and built in in our computer store are all ..."

that's why 2 40s, 2 80s and 2 92s pump the air in front of me * g
oh yes, Viskarte is fine ....

hih
until then

klauswernergaga7

"That's why 2 40s, 2 80s and 2 92s pump the air in at the front g achja, ..."

Moin gaga, my Vi-ka has completely dismantled it, what the heck. Blow in AND blow out, that's it

Anne Radtkeklauswerner

"Moin gaga, my Vi-ka has completely dismantled it, what the heck. Blow in AND ... "

Jo is right. Just pulling out alone is not done either. When a giant fan almost pulls the components out of the socket and nothing else comes in, everything goes through CD-ROM and burner, and they look like something else inside.

mr_drehmomentgaga7

"That's why 2 40s, 2 80s and 2 92s pump the air in at the front g achja, ..."

For me, a really fat 120s front-bottom and eight 40s (hard drive removable frames) front-top push filtered air into the case.
Warm air extraction is done with an 80s at the top and at the middle (near the CPU) an 80s and my Enermax power supply.
And the fan of the Alpha cooler on my P3 1000 sucks.
I bundled all ribbon cables and LVD cables into round cables to improve the airflow. *
Even with hours of full load operation, the CPU remains below 40 degrees.

* I had to install a set of spoilers in my case so that the case wouldn't fly away from me. ;-)))

klauswernerdr.evil

"What is better? Blow cold air on it, or blow warm air away "

There he is again, the crazy guy with the 2 power supply units, But seriously: My PC has a second power supply unit at the bottom, which only operates the drives and the fans and sucks in at the front. In the case there are 2 80s fans, almost exactly at processor height, which keep the 1000 Duron cool and blow it outside. Of course, the CPU also has a fan and the chipset of the Abit KT7 has only been cooled passively since then. In the box it pulls like pike soup, 2 hours of unreal gaming, Cpu-Temp max 40 degrees. It's a Duron, and the case a Big-Tower. Current temperature after 12 hours 33 °