Advice needed on which fans for what

Ultim8 · 1 Oct 2009 at 21:53

Right im nearly ready to build my rig which will consist of the following cooling i wont bother with the components as the list will just go on and on and i will post a proper build log once i get going:

TJ07B-W
480mm TFC Xchanger
240mm TFC Xchanger
240mm Magicool or 240mm Blackice Stealth
X58 Classified full board block
Heatkiller 3.0 CU
XSPC Dual Res bay with 2 x 18W DDC 1 Ultra's
GFX unknown yet gonna wait and see some results first.

1) First off does the blackice fit in the top of the TJ07 without modding it?
2) I was looking at the Noctua S12B-FLX or the P12's which would you choose or can you think of anything better? or would different fans be better on the different rads?

Cheers

Ulti

JonJ678 · 1 Oct 2009 at 21:56

You don't want the S ones for radiators. The noctua P12 fans are popular. Others to look at are scythe gentle typhoon and s-flex, and the apache fans.

38mm will almost always dominate for radiators, so if you don't care about noise the scythe kaze fan would be good. The 38mm san ace are awesome but not that easy to find. I have one, the place I bought from has two left in stock. Obviously I cannot link to them.

Ultim8 · 1 Oct 2009 at 22:01

ah yes Jon i have an mcubed t-balancer so although noise is an issue while the system is idling as its in my living room as long as its quiet while idealing the noise isnt as big an issue when its loaded and im gaming.

And just so im understanding this correctly and the way im thinking is...
The P12 have a higher static pressure so even though the CFM isnt as high the force at which that air leaves the fan is better when restricted ie through rad fins, then the S12B's are ideal for getting as much air as possible out of the case via a exhaust?

Love learning all this

Cheers

Ulti

JonJ678 · 1 Oct 2009 at 22:11

Not quite. A high static pressure will force air through the fins, so airflow through the fins is high. Say 20cfm. A low static pressure fan will be unable to, and will achieve perhaps 3cfm. That the low static pressure moves more air without a radiator in the way doesn't mean anything since there is a radiator in the way. So static pressure is the only number you care about here.

High rpm fans will be better (and louder). Pressure scales as the square of rpm, so 1900rpm is much better than 1600rpm, and 800rpm is a lost cause. Hence the 3000rpm 38mm fans work rather well.

The S12 fans are designed as case fans, yeah. The P12 fans work almost as well as case fans.

Quiet is a bit subjective, but fan controllers will help enormously. As will large radiator surface area, so you should be fine.

Ultim8 · 1 Oct 2009 at 22:33

Ok so fans like the xigmatek for example which are 61CFM @ 1500rpm will have bugger all static pressure compared to say a 54CFM P12.

So really CFM is irrelevant unless your looking to get as much air out of the case as possible via an exhaust.

Where as if your pushing/pulling air through a filter,rad or heatsink (Something with more resistance than air) then static pressure is the key to performance.

Out of interest what kind of db vs CFM are the san aces?

Cheers

JonJ678 · 1 Oct 2009 at 23:03

I'll see if I can find the datasheet, but I've got bad news for you regarding db readings too. The xigmateks might be fine, without knowing the pressure I can't say. I would not be optimistic however.

Generally going for whatever other people are using works well. Yate loons are popular because they're pretty good and cheap, xtreme was raving about gentle typhoons a while ago. I use scythe s-flex most of the time, the noctua P12s are popular too.

db is dependent on distance from source (and ambients). 20db at 1m is very different to 20db at 10m, and the distance is rarely specified. So fan makers can put whatever number they feel like beside db. Much like cfm, you need to know cfm through a given resistance, and without the second number the first doesn't mean much.

My fan has 9G1212H1011 written on it. It isn't quiet, but the noise is quite low frequency. Pushes a ludicrous amount of air compared to 1600rpm s-flex. Found 39 db quoted, and 0.2830 in H2O for static pressure. That's likely to be in cm3 of water.

Ultim8 · 2 Oct 2009 at 00:12

JonJ678 said:
I'll see if I can find the datasheet, but I've got bad news for you regarding db readings too. The xigmateks might be fine, without knowing the pressure I can't say. I would not be optimistic however.

Generally going for whatever other people are using works well. Yate loons are popular because they're pretty good and cheap, xtreme was raving about gentle typhoons a while ago. I use scythe s-flex most of the time, the noctua P12s are popular too.

db is dependent on distance from source (and ambients). 20db at 1m is very different to 20db at 10m, and the distance is rarely specified. So fan makers can put whatever number they feel like beside db. Much like cfm, you need to know cfm through a given resistance, and without the second number the first doesn't mean much.

My fan has 9G1212H1011 written on it. It isn't quiet, but the noise is quite low frequency. Pushes a ludicrous amount of air compared to 1600rpm s-flex. Found 39 db quoted, and 0.2830 in H2O for static pressure. That's likely to be in cm3 of water.

ah i see i thought there would be an industry standard for distance to db levelling. Thanks for all your help Jon its greatly appreciated and i'll let you know what i decide to go for now i understand all the factors