I have an noisier than average cooling fan on one of my systems’ CPUs. It drives my wife nuts! The motherboard doesn’t have the capability (I don’t think - nothing in TFM about it) to throttle the fan based on temp/load. I’ve seen fan speed regulators for case fans but not for CPU fans.
Question - can I put a potentiometer inline with the fan to slow it down?
Obviously, I’d be running Motherboard Monitor and keeping a close eye on the temps. This isn’t a mission-critical box, but I’d prefer not to fry the proc, either.
FWIW, the proc is a 1.2G T’bird. It’s not overclocked, and if I have to resort to under-clocking to keep it cool with reduced fan speeds, so be it.
I’m looking for a cheap solution here as we’re flat broke at the mo, otherwise I’d go buy a new board/proc. I read somewhere that the Tbird series are some of the warmer-running units out there. True?
You are trying to reroute the plumbing when all you need is a new faucet. All you have to do is replace the fan. They are very cheap (like less than $10 for a basic model but you may want to look for an extra quiet model for a little more). It unclips off of the CPU and has one power wire running to the motherboard. Unclip - Click New One - Plug in - Done.
They have dozens of fans listed at all different speeds, prices, and quality. Note that link has many pages of selections sorted from lowest to highest price.
There are devices specifically for controlling computer fans–they can be set to operate totally manually (at whatever speed you set them to) or can run in a temperature-sensitive mode, where they speed up in response to increased heat. I don’t know much about the details but they are a pretty common accessory in getting a PC to run quiet by replacing/controlling the fans.
Look around here: http://forums.silentpcreview.com/
-or the companion site, which reviews such equipment… If you look at the “general gallery” forum there you will see people’s computers with these 5.25" bay panels that have several knobs on them, the knobs are fan speed dials.
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That’s exactly what I did on a PC, because I couldn’t find a fan that was quiet enough. I fitted the potentiometer so that the little knob sticks out through a hole in the back of the case. You have to get one with an appropriate resistance range of course. I can’t remember what mine is, unfortunately. It says 100R K on it, if that means anything. I got the details from a website devoted to silencing PCs. Even with the fan at its slowest, the CPU temp stays below 45C.
I’m hopeless with a soldering iron and know almost nothing about electrical stuff, so if I can do it anybody can.
You can just use a regular potentiometer, or even just a resistor. Some “quiet” fans come with an optional resistor insert–I have one on-hand, by the by, [I’m too lazy to post a pic, but I think it came with a Papst fan]–its colors are green, blue, black, gold, and it looks kinda big, 2 or 5W maybe. The resistor body is about as big as a regular medicine capsule. It’s on a 3-wire harness, and the black and white wires run through normally–so the red one has the resistance on it.
…but…
The problem with just using a simple resistor is if you play games, particularly 3-D action games. These put a HUGE load on the CPU and videocard, and you could run into overheating problems when you are playing them. That’s the justification for spending money on the “automatic temperature-sensing/fan-throttling” business.
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It means 100 K Ohms. If that “R” is actually an “A” then it’s an audio taper.
Basically pots come in two types, audio taper and linear taper. In a linear taper, the resistance changes directly with the amount you turn the pot. In an audio taper, the resistance changes according to a logarithmic curve, which is more what your ear hears as “linear” even though it’s not. In this case, since you aren’t dealing with audio signals, a linear pot would be better, though either one would work.
I’m not very fond of the pot idea, though if you are certain you are keeping the CPU under 45 deg C even under the heaviest load then I suppose it’s ok. Personally, I would replace it with a quieter fan instead of mucking around with a pot.
Thanks to all who replied. I’ll try a 100k pot (seems like linear taper would be the way to go, though). I have another fan - it’s a ThermalTake TT-6025A. It’s rated at 28 dbA, which has GOT to be a crock. Maybe if it was measured 1 metre away from a lead-lined case. My Radio Shack SPL meter only reads from 60 db on up (just found out one of the machines at work (not a PC!) peaks at 118db - glad I was issued hearing protectors) so I can’t disprove the 28db claim, but it IS louder than what’s already in there. This is why I haven’t bought another fan - not only is it two hours’ wages (I’m in New Zealand, we don’t have NewEgg here) but I can’t trust the specs on the box.
The PC is a micro ATX Biostar stuffed in an Apple IIGS case. It won’t be used for gaming but for a win98 legacy app that I can’t get to run on 2k (USB DATport). Very low-load and occasional use.
Let’s not get into chipset fans. The one that came on my Asus mobo screeched to death within a week. The replacement was noisy, so I just unplugged the confounded thing. Three years later, stable as a rock.
Ummmm guys–we’re talking about a 12-volt motor here. A 100K resistor is a bit much; the green-blue-black resistor is 56 ohms. Maybe try a 100 ohm pot if you want–but note that part of the practical problem is that a motor usually needs more power to start up than it does to run. If you adjust your pot for the slowest possible running speed, your fans may not start rotating at all the next time you reboot. That’s the reason that people who want manual fan speed control install the front-panels that have the adjustment dials there…
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