Should the fan blow or suck air?

[Pla]

The airflow direction through the rad will be the same.
Which way is more efficient - blow or suck air?
Any observations with your system?
The only think I can think of are these 2:

1) The air flow may be more in one of the cases.
2) The air should be cooler when sucking it because its presure is lower.

Anybody tried? Any differences in themperature?
Thanks for any comments.

 

[SkiFletch]

best way to do it is to try and use outside ambient air to cool it, instead of case air. whether its blow vs suck usually only makes a .5c difference in temps. provided the air always comes from ambient, it shouldnt matter either way

 

[The Spyder]

BOTH..... i would have one pulling in and one pushing out

like this
Case front~ fan~ rad~ fan~

 

[Warlord2]

yeah both would be best but if you dont have that luxury thin have it pull air from outside the case.

 

[Stalka]

should suck air from outside the case through the rad or whatever...

 

[Pla]

Thanks for the advises.
My rad is outside the case so the air is optimal. I'll place the fan to suck air and will post the result later.
Thanks.

 

[Pla]

It gave me 2C lower when the fan was sucking. This is too much difference.
Somehow the airflow is a little better - the RPMs of the fan are lower for the same voltage so the airflow must be higher. (If I cover the fan the RPMs go higher and the airflow is 0.)
It may be just result of less dust...

 

[Toysrme]

It shouldn't make much of a difference if it's outside the case. Either way the fan will have to fight the heater core to suck/blow air through it.

If it's in the case, then I would take it as a case by case basis (no pun intended)

On the one hand the radiator will run cooler from outside air pulled in giving you a better cpu temp, but higher case temp. (assuming you have adequate case airflow already)
However if you blow air out your CPU temp will be greater, but if you don't have enough exhaust fans to begin with then your case temp will lower.

-Toysrme

 

[JFettig]

I did a simple test a while back, an 80watt peltier, and a heatercore, I tested with a fan blowing with a shroud, without a shroud and sucking with a shroud, blowing and sucking were exactly the same and without the shroud it was up a few degrees

 

[JFettig]

Its kinda whatever works best for you