Best CFM in a 120mm Fan?

tirefire

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Jul 16, 2006
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Hey all,

I have a PC with a Cooler Master Centurion 5 case. It came with a 120mm fan already installed to blow air out of the rear grate. However, the fan barely pushes any air at all. My old PC had an 80mm fan that made quite a breeze if you put your hand behind the tower. This one is pathetic. I've tried connecting it to the motherboard as well as a molex connector, and neither one makes it blow very much.

Do any of you own a nice high-CFM 120mm fan you could recommend to me? I could probably solve this problem by investing in 3rd-party heatsinks, but I'd rather buy a $5 fan and put up with the extra noise.
 
I like the Panasonic Panaflo case fans. The 120mm fans come in 3 different fan speeds and cfm. The fans are thicker than typical fans and the pitch of the fan blades is different than most fans allowing for a higher cfm rate. I never had any problems installing them in mid-tower cases.
 
Smokedyou911,

I've got four 120mm Panaflo fans rated at 115 cfm in my new rig that I am assembling. I am growing old disgracefully and I'm a little hard of hearing so I don't hear the fan noise like young people do.

Cables are kept to a minimum thanks to a Corsair modular power supply. The cables are tied down and out of the way. I eliminated the hard drive cage in the bottom of the case. The hard drive is mounted directly behind one of the two fans in the front of the case. I have one heck of a wind tunnel effect.
 

IcY18

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In a test done over at xtremesystems.org they found the Panaflo and Sharkoon fans to be the best. Sharkoon are harder to find and don't have ultra high output fans like Panaflo does but they are quieter than Panaflo's mid level output cfm ones.

Check out the Sharkoon Silent Eagle 2000.
 

double_helix

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Remember, though, that 120mm fans have higher CFM than a 80mm fan at the same RPM. 2000-2500RPM can push 80 CFM at 120mm easy, while an 80mm fan at the same RPM only pushes ~30 CFM. So to compensate for the smaller displacement ratio, 80mm fans have the spin faster thereby pushing air harder.

In example, the 80mm fan would have to spin at 5333-6664RPMs to have the same amount of CFM as 120mm spinning at 2000-2500RPM. This is why 120mms don't seem to be moving air as much as an 80mm. There's more variables like the lenght and pitch of the individual blades that can also impact CFM performace.
 

tirefire

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Thanks for the input, guys. I think I'll order an S-Flex next time I order something else from Newegg.

And double_heli ix - I see what you mean about the CFM-diameter-RPM relationship, but this case fan I'm having trouble with is nothing short of anemic; my processor is overheating enough to crash programs because of the stagnant air in the case.
 

lensman

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I have the Scythe S-Flex F's that Spikke mentioned and love them. I have a fan controller so I usually leave them on low and can't hear them at all. I turn them up when I'm gaming and know that things are going to heat up.

Watch out for the fact that there are three different S-FLex'es the D, E and the F. The F's push the most air but are the noisiest. The D's and E's are virtually silent.

Another thing you might check is whether the fan grate is disrupting the airflow. You might just have to doctor the fan grate up to improve your existing fan's airflow.
 

Kamrooz

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I'm planning to get the Scythe s-flex's for my new rig. With all the rave about them they have to be good. If you want to buy just one it'll set you back 20 dollars..The silvertones I mentioned on newegg are 17.99 and push 110 cfm's...I have 2 in my case now..loud at the full speed...39.5 dba..but great at movie air..

the scythe fans actually have a bulk purchase on newegg..you can get the lowest cfm and highest cfm fans on bulk order for cheaper. They cost 19.99 but I have to buy 9 of them for my new rig I'm getting with a coolermaster stacker which holds 9 fans...if I buy 6+ then come down to 11.49 each compared to the 19.99 they usually are...Great deal if you want to buy mass amounts. ^_^..

don't know how long it will last..so go for it quickly if you want a few of these.

http://www.newegg.com/Product/Product.aspx?Item=N82E16835185006

tha t's the link...2 fans drops the price to 13.99...so you save quite a bit..the more you get the cheaper..until 6+..then it's the same price for all.
 

IcY18

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They are also 3x the thickness of standard size 120mm fans and they also are about as loud as a vacuum cleaner, seriously.