• Welcome to Overclockers Forums! Join us to reply in threads, receive reduced ads, and to customize your site experience!

Radiator Fans: CFM vs. Noise vs. Cooling?

Overclockers is supported by our readers. When you click a link to make a purchase, we may earn a commission. Learn More.

silvrhand

Registered
Joined
Oct 5, 2004
Has someone done any testing to find out if there is a sweet spot for the amount of CFM to push through a radiator? I got some delta fans and they are way too loud but they push a lot of air, but I'm not sure if they are really giving me much of a performance boost as I built a new machine basically when I put the fans on.
 
Do you have some older fans that might be quieter and less powerful to try out? I have a pair of san ace fans that I run at 7v. At 12v, they're pretty loud but the return was barely noticeable. BTW, I have a Black Ice Extreme 2-120.
 
depends on the radiator.


on my mcr320 is rivals other rads when its at low rpm, beats out pretty much every black ice rad. but when you put 100+ cfm fans on it, the black ice will come out on top.


and same goes with the thermochill, with low cfm fans its god like. at higher cfm's the black ice slowly catches up and then beats it. but you need a lot of cfm's.



in my opinion, if your fine with the noise, keep it. no one really knows the "sweet" spot, i think its more preference.


my sweet spot is just as many quiet yate loons as i can get. and just let the run at full power and let all the db's add up and leave it at that.
 
There is a point of diminishing returns on increasing airflow, but it is going to depend on the design of the radiator itself. There are various radiator graphs online, but without knowing what rad you are using we are left kind of hanging.

As for the sweet spot, you can always just undervolt your fans and see what difference it makes in temps and then just go with whatever seems comfortable for you. For me, my PA120.3 with yate loons at 4v is good to me as it makes almost no noise.
 
Black Ice Extreme III

Sorry I wasn't quite sure either had to lookup my parts order. Been a while since I had no problems on the AMD FX55, but with the new 680i board and the case, I've had to go through a lot of rework, and still have some things to figure out.

The 680i southbridge is nasty, lots of heat generated but very problematic as it's right under the PCI-E slot, the primary one too so you can't use the bottom one.

I was actually thinking about getting two of these to try to go radiator less.. and hook them up in line on the side of my PC. I've really gotten used to the lack of noise but with the new delta fans on my rad I'm not really happy with the noise level.

http://www.xs-pc.co.uk/res500.php


voigts said:
There is a point of diminishing returns on increasing airflow, but it is going to depend on the design of the radiator itself. There are various radiator graphs online, but without knowing what rad you are using we are left kind of hanging.

As for the sweet spot, you can always just undervolt your fans and see what difference it makes in temps and then just go with whatever seems comfortable for you. For me, my PA120.3 with yate loons at 4v is good to me as it makes almost no noise.
 
I doubt that is going to work very well. Yate loons at 4v on a fan controller like mine are VERY quiet, as in below ambient room noise level.

The BIX is thicker and is going to work better with higher cfm fans. The Black Ice Pro is better for lower cfm fans (sidewinder has the 3x120mm for only $38+ahipping right now).

If are really determined to go totally silent, then a copper core car radiator is going to be the way to go.
 
Wonder how much water it would take to not have a rad at all, would 10 gallons in a metal tank or something on the floor be enough? I could actually submerge the Eheim pump inside and just pump it out of a square tank forever.

voigts said:
I doubt that is going to work very well. Yate loons at 4v on a fan controller like mine are VERY quiet, as in below ambient room noise level.

The BIX is thicker and is going to work better with higher cfm fans. The Black Ice Pro is better for lower cfm fans (sidewinder has the 3x120mm for only $38+ahipping right now).

If are really determined to go totally silent, then a copper core car radiator is going to be the way to go.
 
silvrhand said:
Has someone done any testing to find out if there is a sweet spot for the amount of CFM to push through a radiator? I got some delta fans and they are way too loud but they push a lot of air, but I'm not sure if they are really giving me much of a performance boost as I built a new machine basically when I put the fans on.
Everything you asked about and alot more.
http://www.matbe.com/articles/lire/146/comparatif-de-27-ventilateurs-120-millimetres/page26.php
from:
http://forums.procooling.com/vbb/showthread.php?t=12581&highlight=how+to+choose+the+best+120
 
You could also try 1or2 Mechatronics AC Pc fans You can just about hear them,and they push alot of air.I'm using 3 120cm Mechatronics as well as 1 300mm Crossflow. I've got one in the front,1 in the rear,and one on the side fan cage door on the side of the cross flow. They brought my two GTS's temps down from 62-64c to 50 -52c.I ran the AC plugs through the wire mesh on the bottom of my case.
 
silvrhand said:
Wonder how much water it would take to not have a rad at all, would 10 gallons in a metal tank or something on the floor be enough? I could actually submerge the Eheim pump inside and just pump it out of a square tank forever.
the problem with that is...

A. You have a HEAT source in the water (the pump) and they do get VERY warm.
B. You have no active, or decent passive way to cool the water.
C. Under this circumstance (no radiator) your best best is to build a bong type cooler.

Mine I built for literally about $40. I also got the primer and GOOD clear sealer.
1 5' section of sched 40 4" 5.65
2 4" 'wye's 8.95
1 4" 'T' 8.95
3 4" caps 1.95 ea
Purple primer 4.95
Clear cement 3.95
I added a sight guage to mine using 2 brass barb fittings and some clear line 1.95 ea.
3/8-1/2" barb fitting 1.95

The shower head is a 1.97 deally from wally world.
Ambient is around 71F so 20-21*C the probe in the water stream reads from 11-15*(load depending) so it is well below ambient.

The down side, it can evaporate up to 2 liters in 12 hours. So I fill in the morning and fill at night.
 
Back