Curious about variable speed 120mm fans

[Spike]

Ok, I just got a Thermaltake 480watt and put it in my antec superlanboy that has been sitting around for a few monthes. After transplanting my computer (2500+ @ 3200+, Abit NF7-S) I am pleased with the temps and noise level after my old steel case with 5 80mm fans.

I am concerned about the summer monthes, my CPU temp was getting up to 50c under full load after a few hours and while that is completely fine for me, I figure I can add 10 degrees at least to that during summer. I would like to get variable speed 120mm for the case so I can crank it up when gaming in july but am not sure about the setup. Also, I will be putting in a BFG 6800 GT soon, so that will increse my internal temps (I plan to get a NV silencer sometime, though that may not be for a while)

I did some web research and found that you can hook any fan to a speed controller and it will change the voltage. What are two good high speed 120mm fans (90+ CFM) that could be reduced to 25ish Db at the lowest setting on a controller? Also, how does a 120mm fan hook into the controller and still get power? Does the psu hook into the controller, then the controller into the fans?

Oh, one random question, can anyone see why a thermaltake 480watt should have any issue supplying enough power to a A64 3500 or higher? Just curious...

-spike


EDIT** I would also like any suggestions on panel controllers (would like temp as well as a min of 2 fan speed dials) and a good place to get this and fans.

 

[BonzaiDuck]

I can't authoritatively answer a question about the AMD CPU and power requirements only because I'm not an AMD jock. But the ThermalTake Purepower 480 should be enough. I have a couple of these 480's -- not the very best choice I could make, and some people sneer at them, but the voltages are rock-solid and within 1 or 2% of spec. The 12V rail would seem anemic as providing only 18 amps of current, but I haven't noticed any lack of power to either the 12V P4 plug on the mobo, the 120mm fans I'm running, or anything else. It is perfectly adequate.

As to the fan choices. Both the ThermalTake Blue LED 120mm and Silverstone 120mm fans are variable speed, either connected to the rheostats provided with the fans or to a controller. Both of these fans have a slight motor-whine which disappears somewhat when you tune down their top speed (between 2,600 and 3,000) to around 2,000 to 2,200. The TT provides about 94 CFM and the Silverstone provides 104 CFM.

Other fans worth looking into are a Sunon 120mmX25mm with three-pin mobo plug (with monitoring) which pushes (some say 98 while others say) 90 CFM at 3,100 rpm -- noise in the low 40's dB at top speed -- but keep in mind that faster, higher throughput fans that can be adjusted will lose noise at lower speeds and commensurate throughput.

Some 120mm fans are 38mm thick, providing low noise but no monitoring -- the Sunon KD1212PMB1-6A and the YS-Tech. It is important to add here that even if the fans provide no monitoring, they can be run at varied speeds through a rheostat fan controller -- you just don't know for sure what rpms their running.

There is a Panaflo that we have mentioned here recently (120mmX25mm) which pushes about 89.5 CFM at modest rpms and dB's in the 30's. It has a three-pin mobo plug and speed-monitoring capability. The YS-Tech pushes a maximum of 125 CFM's with only 45 dB of noise, and the rpms are only in the high 2,000's.

You have to decide whether you want a simple rheobus controller without speed and temperature monitoring (see the Sunbeam Rheobus -- very reliable and enough power on each channel for several fans), a controller with speed and temperature monitoring (CoolerMaster Aerogate II, for example) or a programmable controller that will increase fan speed according to tape-on thermal sensors applied to mobo and hard drive components (Silverstone Eudemon). There are some newer entries that may supercede these examples. One company has a USB-controlled PCI-slot card (doesn't fit in the PCI-slot itself, but occupies a PCI back-plate.) This allows for programmed, software controlled fan speeds by on-board motherboard or CPU temperature monitors, and -- I think -- has additional plugs for tape-on thermal sensors.

You want to choose fan controllers that have a higher wattage (power) capacity per channel. I believe the Sunbeam provides 20W per channel, which is "beefy". The Aerogate II provides more like 15 to 18W.

The reason the per-channel power capacity becomes more important is that you can connect several fans in parallel, using a single 3-pin plug to connect them to the controller.

Some fans have a "start" voltage below which they will not spin up, but this value is typically 7V, while many fans have start voltages as low as 5. The variation of fan speed would fall within voltage variation between 7 and 12.

Most fan controller models including the front-panel 5.25" variety use one of the 4-pin power-supply Molex plugs, transferring power to the fans which are usually connected by smaller 3-pin plugs and accommodating the speed-monitoring wire. Some kits come with these 3-pin plug wires with a 4-pin Molex adapter for fans that have a 4-pin Molex tail.

Enermax also makes a 120mmX25mm fan that has its own speed-control rheostat like the ThermalTake and Silverstone, but as quiet as it is -- it only uses 0.30 Amps @ 12V and spins at a maximum 2,100 rpm -- its throughput is lackluster, and frankly, I think it sucks. You'd do better to find a 0.40 to 0.66 Amp fan with high throughput that can be tuned down within some range of throughputs, speeds and noise-levels.

 

[Spike]

Thanks a ton for the reply BonzaiDuck, that answers alot of my questions.

My setup will be very simple, I have only two fans I will want to control at the moment, so (if I understand you correctly) almost any control panel will do as I won't be hooking multiple fans to a single variable resister. I was looking at this model

Controller

Mainly due to it's price and temp display. Though I like many of the Enermax models as well. I am not concerned about monitoring RPM, only want to be able to adjust a fan from nearly silent to rock and roll when I need the air flow. I would idealy like to have a range thats starts out down to what my Antec fans run at right now (~1200 rpm, 38cfm, 24 dB) and goes up to around 70-90cfm at 40-45dB max. I am more concerned about the lower level for winter operations and web-surfing mode, if the high speeds are super loud that is ok.

I have looked at the YS-Tech fans for their insane amount of air flow, but I wonder about how they sound on the lowest settings of the pot, would it be above my current 24 dB? That panaflo you mentioned (I assume that is the H1A?) sounds about right, if at high RPM it is only in the 30's, I would assume at low RPM it would be whisper quiet (low 20's).

Thanks again for your help

 

[BonzaiDuck]

Yes, the Hardcano 9 is nevertheless a standup controller if you keep the total draw to something less than 1 Amp per channel. The precise numbers are in the instruction pamphlet, but that's about it. Figure each channel is then rated at about 12 Watts.

I had one -- the rheostats are of high quality. You get one temperature sensor only. Also, I think it is recommended to put the fans with the greater power draw -- totaling something over 0.35 Amps -- on channels 2 and 3, leaving 1 and 4 for less demanding fans.

I was mistaken about the Panaflo insofar as it is 120mm x 38mm -- a "thick" fan like the YS Tech or Sunon KD1212PMB1-6A.

I've tested many fans, but there are many more out there I have yet to touch. Somebody mentioned "Globe", which first came to my attention in a heatpipe-cooler review.

It would be nice to have a completely noiseless fan that cools effectively and moves a lot of air. But I think the most you can expect is an absence of motor noise, and you deal with the air-turbulence through your choice of fan deployment within the case and any ducting enhancements. I personally chose to use Akasa PaxMate noise deadener in my case, and it really helps. Some would argue that it severely degrades the case metal panels acting as a heatsink, but my systems are pushing so much air through the cases anyway, there is little need to worry about it. Also, if you use PaxMate in the most effective manner (which entails putting a sheet of it on the accessible left-side case panel), you would have to settle for "no Lexan windows" on the case.