which way should a cpu fan blowing?

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26-09-2003, 08:20 PM
BroadbandPlacey

which way should a cpu fan blowing?

which way should a cpu fan be blowing, towards the heatsink or away from it?

i have very high cpu temps and wondering if thats why?

cheers
26-09-2003, 08:35 PM
Austin

;) Virtually always blowing down on to the HS, check with the arrows marked on the fan. You can try it both ways and see what is better in practice though. Don't worry too much about reported temps as they're a rough indication only ... if you're stable don;t worry.
26-09-2003, 08:42 PM
BroadbandPlacey

well its blowing away from the the cpu, ill reverse it, and hurl abuse at the stupid git who put it on the wrong way.

cheers

it was at 63 degrees but ive got it down to 53, still too high for my liking.
26-09-2003, 08:57 PM
fondie

yep, definately make sure it's blowing air towards the cpu, if you have the fan blowing away it leaves a dead zone, where there is very little airflow, right at the centre of the cpu (which is the most important thing to cool effective)!
26-09-2003, 08:59 PM
BroadbandPlacey

does it also matter a great deal that the heatsink isn't positioned in the center of the cpu, its off center.
26-09-2003, 09:00 PM
Knoxville

aye definatly blowing towards the cpu, i've made that mistake meself :/
26-09-2003, 09:34 PM
Nemeliza

If you wanted a fan to cool you down would you stand infront of it or behind it, same theory. (in most cases anyway)
26-09-2003, 09:58 PM
Howard

Pretty much every heatsink/fan kit comes with the fan blowing towards the CPU, why would you have it the other way anyway :confused:
26-09-2003, 11:04 PM
ibmike

depends on system m8 some work better blowing onto cpu others away
trail and error
27-09-2003, 02:00 AM
Austin

Quote:

Originally posted by Howard
Pretty much every heatsink/fan kit comes with the fan blowing towards the CPU, why would you have it the other way anyway :confused:

;) Some of the expensive HS don't come with fans ... another common reason is people cleaning the fan and then forgetting which way it went on or accidentally putting it back the opposite way. Certainly 99% of the time you want the fan blowing air down on to the HS but if in doubt test as ibmike suggests.

:D BroadbandPlacey, it doesn't really matter so long as the HS in firmly attached and ideally covers the whole CPU (certainly the core LOL).
27-09-2003, 05:37 PM
KVandal

50 degrees is still pretty hot, is that in load or idle? if idle, id b worrying. Check the airflow through the case, do you have a system fan? also, tidy up those cables, might be worth picking up a pair or round IDE cables- these will help. Another thing, you could always pick up a new CPU fan, these cost around a tenner and if you want some serious cooling, get something like the Vantec tornados shown on here:

http://www.overclockers.co.uk/acatalog/Vantec.html

They have very high CFM output, but are rather loud! alternately, Thermaltake do some powerful ones:

http://www.overclockers.co.uk/acatal...altake_64.html

just make sure the air is circulating nicely in the case, if the cpu fan was on wrong, mite b worth checking the intake and exhaust ones too, make sure they are all correct!

KV
27-09-2003, 06:18 PM
Austin

:cool: Fans at Dabs:

http://www.dabs.com/products/prod-se...p=&up=&mc=&sc=

;) £10 is steep for a Case Fan 2, you can get a Volcano11+ HS with Smart Fan 2 for £15 at Dabs which would make more sense, full adjustability is well worth it, HS design also counts for a lot though.

:p Vantec's case fans; Tornados unusably loud while the Stealths don't move much air. The Thermalflow may be the happy medium! Vantec 's Aeroflow use TMD (tip magnetic driven) which makes it more efficient than conventional fans. As a result, the Aeroflow is reported to perform very well at a reasonably quiet noise level. Well worth a look.
28-09-2003, 02:40 PM
eldren

The Aeroflow is still fairly noisy (I have one), but seemed significantly quieter than the other computers at a LAN yesterday (I couldn't tell when my PC was off, had to check the lights). It's my whiney Maxtor I want to kill for depriving me of sleep. x.x
28-09-2003, 06:48 PM
Vijay

Hi,

This will sound stupid but all the Comps I have seen seem to have the fans pulling air out of the heatsink and acting like exhaust fans. This may be because I am in India and the ambient temp is much higher than in the UK.

Could the forum gurus please confirm that the fans should actually be blowing on the CPU and not acting as an exhaust fan?

Also is there any thing about this on the AMD site if so could some one provide an url/details etc?

The reason is that my CPU shows temps in the mid 60-70 range and I feel it is running hot possibly because the fan is mounted wrong.

Thanks,

Vijay
28-09-2003, 07:01 PM
KVandal

as the other lad said, if you wanted to be cooled down, would u stand infront or behind a fan. try it and notice the enormously crap cooling you get behind it.
28-09-2003, 07:02 PM
doopydug

I wouldn't have thought the ambient would make much difference mate. Whether it sucks/blows air is the important thing and it is better blowing onto the HSF.
28-09-2003, 07:32 PM
BroadbandPlacey

cheers all,

i hadnt thought about standing in front, behind a fan, good analogy (sp),

hs does cover all of the cpu, but hangs over a long way at the other side,

have bought a 5.25 bay with fans in to bring cold air from the front, at the mo all the hot air is at the back,

another case fan, 3 in total now, (LED fans, ie, low performance)

it all arrives later this week, how i love ebuyer, will tell you how it alters heat.

all the leads in my case, ie, IDE are all hidden due to my case having a window,

its 53 degrees on fully load, not much less on idle.

i think thats an answer to everyone's questions.

cheers again
28-09-2003, 08:19 PM
m0dm0

i made that mistake before as well (ages ago :p)

m0.
28-09-2003, 09:43 PM
mightynimrod

If you have an Alpha Pal 8045 it says to fit the fan blowing away from the heatsink...i've always had it blowing on to it so i might try it the other way round (blowing away) to see if it reduces temps.
28-09-2003, 10:06 PM
Austin

Quote:

Originally posted by KVandal
as the other lad said, if you wanted to be cooled down, would u stand infront or behind a fan. try it and notice the enormously crap cooling you get behind it.

;) Precisely, it still makes sense to give it a try but I would severely doubt the 'blowing away' techique would be the better option. The idea of exhaust fans isn't to cool your case air down but to remove the warm air which will obviously help introduce cooler air via intake or ventilation.

:cool: eldren check out Maxtor's site for Acoustic Management Software, it adjusts the drive's firmware for 3 diff modes. Firstly OFF (default) which is max perf (to hell with the noise), FAST which is as much perf but with less noise and thirdly QUIET which puts noise as the top priority. Well worth checking out.