I'm curious if I was to hook up the tornado to a fan controller and run it at lower rpms how much cfm would it put out. Can I divide the rpms by cfms and use this ratio to find out or does it not work like that? It runs at 4800 rpms and moves 119cfm so I was thinking if I ran it at say 3800 rpms it still should move more air than the 50cfm my current fan does(by my calculations 94cfm) and not be much louder....

Alright, I'm going to make this simple.
Tornadoes are loud.
Damn loud.
I run mine on a Vantec Nexus fan controller at the lowest setting and it's still about 5 times louder than any of my friend's computers. Combined.

Quote: Originally Posted by DuplexEmotions Alright, I'm going to make this simple. Tornadoes are loud. Damn loud. I run mine on a Vantec Nexus fan controller at the lowest setting and it's still about 5 times louder than any of my friend's computers. Combined.

What kind of temps do you get on the lowest setting? Around how many rpms is that?

Quote: Originally Posted by swtguy What kind of temps do you get on the lowest setting? Around how many rpms is that?

I have one as a case exhaust fan(friend gave it to me too loud for him) running off a 5v line, and have a large potentiometer on it to drop it down even further, then its quiet..but barely moves any air..its still pretty loud when running the full 5v, no CFM or RPM data though...
I just use it at the full 5v when going for max overclocks..I leave it at low settings for daily use.

you cant devide it by the ratio, because as the fan spins faster the air moves faster, and increases at a faster rate, like if it was a line graph, it would be curved.

don't know the RPMs, 35C load with stock AMD heatsink.

See attachment for fan laws.

Yes, the volume of air moved (CFM) varies directly with RPMs, but I don't see how you know the RPMs with a simple fan speed controller....or CFMs for that matter. It's all just estimation...which really doesn't mean squat.

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Quote: Originally Posted by lAnonymousl See attachment for fan laws. Yes, the volume of air moved (CFM) varies directly with RPMs, but I don't see how you know the RPMs with a simple fan speed controller....or CFMs for that matter. It's all just estimation...which really doesn't mean squat.

Exactly..The best way to deal with fans is with a fan controller, if your concerned about noise levels, A Tornado at full bore is like sitting next to a loud shop vac...

If you all ready have the controller, then there are a few things you can do.

Put you hand an inch or two by the fan (With a fan grill on it of course!)and "Feel" the airflow..vary the RPM of the fan, and see what its like..and balance that with the noise levels your ears can deal with lower is better for every day use of course..I turn the clock speed down a bit, and leave the fans on low..Just keep an eye on your temps...
Bigger sized fans can move lots of air at lower RPM, and can be much easier on the ears, but sometimes involves modifying your case..but thats what PR is all about

So when ya need more cooling for Gaming, Overclocking or whatever.. you can always turn up the "Noise"

Nooooo The Shift Fuction Won"t Go Away Nooooooo!!!!!!!

Quote: Originally Posted by lAnonymousl See attachment for fan laws. Yes, the volume of air moved (CFM) varies directly with RPMs, but I don't see how you know the RPMs with a simple fan speed controller....or CFMs for that matter. It's all just estimation...which really doesn't mean squat.

Thx for that attachment. I figured there was a better forumla for it then the way I was doing it. I realize it's all just estimation but i'm just trying to figure out if it's worth buying a 92mm tornado to replace my enermax 92mm fan. If I can get more cfms with just a little increase in noise i'll go for it but if it's going to be close to the same then I don't want to bother.

Quote: Originally Posted by $SOLID$ Necro Exactly..The best way to deal with fans is with a fan controller, if your concerned about noise levels, A Tornado at full bore is like sitting next to a loud shop vac...

4 tornadoes at full bore = People refering to your computer as 'the hovercraft'.

for fun at LAN parties I float CDs over the blowhole.

Quote: Originally Posted by DuplexEmotions 4 tornadoes at full bore = People refering to your computer as 'the hovercraft'. for fun at LAN parties I float CDs over the blowhole.

Wow what kinda temps you get with that?

I run mine at full blow on my thermalright, because I am A) too lazy to go get a speed control and B) like to annoy my brother with ear piercing goodness.

swtGuy: I get about 35C load with them running at 7v, 30-32 C under load at 12v

coldest I've ever gotten it was 2C with them at 12v..... it was sub-zero at that LAN party, though.

actually there are a few other factors involved.......fan design and the fan shroud.....
If you want an acurate cfm reading on the fan, find someone who owns a race car shop that "flows" (ports & polishes) heads then they can hook-up a manometer, which is used to measure flow (either air or water).