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aeonflux707
10-31-04, 01:39 AM
The heatsink fan, should it be blowing air to or away from the cpu? LOL. I don't know so I'm going to ask! ;)
aeonflux707
10-31-04, 01:42 AM
?I don't know
Tecleaus
10-31-04, 01:50 AM
i was about to ask the same thing...
gokusimpson
10-31-04, 01:54 AM
Mine blows into the heatsink. I think all of them do. Unlike video card coolers.
Tecleaus
10-31-04, 01:55 AM
if video card coolers blow out then should i have the fan on the side of my pc sucking air out or blowing air in??
gokusimpson
10-31-04, 02:04 AM
They should blow out. I have 3 80mm fans blowing out, 1 psu fan out. I have 2 40mm fans blowing in. You want negative pressure.
Crax
10-31-04, 03:10 AM
It depends. Some heatsinks like air blown on them for more active cooling, while others like it to be pulled away and blown off and away from the mobo. Video card heatsinks are a little different sometimes because they usually cover a larger surface area. I dont know the designs behind all of them, but from what Ive seen, some suck and some blow. My video card fan sucks (its good, but yeah... you know what I mean.) The fans on the side of your case really doesnt matter, it depends on the rest of your setup, but mine sucks in, but if you have the HSF blowing away from the heatsink it would be just as good to have that extra suck and turn the side fan around. If that makes sense, I dunno, its late.
Rudegar
10-31-04, 06:09 AM
most cpu fans blow
all the video cards i've had also blow
and with case fans then heat travel upwards
so the fans who suck air into the case should be set low
and the ones you blow air out should be set high up
Crax
10-31-04, 06:26 AM
An interesting idea that I developed while in science class this week... The reason hot air rises, is because it is being pushed by the cooler air falling. My theory is that if you happen to have a few extra fans laying around, and you could rig this up it would lower temps even more. Picture this: Three fans on the top of the case... the 1st and 3rd sucking air in and being vented right to the bottom... The middle blowing air up. Forget the rest of the fans all together. With this little cycle you are getting your flow, plus pushing that hot air up even more and blowing it out. I dont know if this would work, but Im sure as heck gonna try it sometime.
therealwesty
10-31-04, 10:00 AM
Fans on heatsinks should blow onto the heat sink. You get a lot more airflow blowing air down onto the fins and dispersing it out the sides than trying to such the air through the fins.

The case though should have slightly negative airflow, more blowing out than in. Best to think of it like this... If you are blowing 30 cubic feet per minute (cfm) of air out the back of the case than 30 cfm has to be getting in somehow (gaps between optical drives, vents etc). BUT, you can't force more air into the case than there is volume.
Colin
10-31-04, 11:58 AM
Negative air pressure in the case is alwasy good... Like westy said the air blowing out will cause a small vaccuum which pulls air into the case via all the cracks and such. :)

As for the heatsink, if you're using a shroud like on Alpha heatsinks then pulling is better, it forces the air to come from the bottom of the heatsink. If you don't have somehting like that then push is best.