Fan speed controller and temperature monitoring questions.

[qat727]

The computer I'm running is a PC my uncle built for me. As it stands, it has multiple fans that run full tilt any time the computer is on. Since I'm not much on gaming and whatnot, it doesn't have all the fancy graphics cards and stuff. Not a bad computer, just enough to run AutoCAD.

Basically, my problem is that my computer is in my bedroom with me, and the fans are loud. Additionally, they suck in all the dust in the room and create one hell of a draft that freezes me during the winter at my desk.

I want to control the fan speed in a manner similar to the way my old Compaq was. The fans would turn off when the computer was idle, turn on at a slow speed for most use, and go full tilt when you were really using it.

I would think that this would be thermostat or thermocouple based. After doing some research, I thought about using something like this: http://www.newegg.com/Product/...95011

Another thought was to daisy chain the fans and use a single rheostat to control speed. Either way, it leaves me with the same problem: temperature control.

As best I figure, if I keep the temperature inside the case below 50* C, I should be fine. I know there are fan controllers out there that have temperature sensors integrated, but I haven't found any that are in my price range ($20 or less).

Given the fact I don't use the computer for much more than puttering around the internet and IM, could I get by with a rheostat control of the the fans and no temperature monitoring, and just crank the fans up if I'm going to really be pushing the computer?

I had considered the other alternative low cost option of adding a mercury switch style thermostat with an override relay to kick the fans on full tilt if the case temperature became excessive, but I wasn't sure if it would be necessary.

If any of you are familiar with this subject and can shed some light on the matter, I'd appreciate it.

[MinisterofDOOM]

Check out SpeedFanhttp://www.almico.com/speedfan.php

[Looneybomber]

Since your Mobo doesn't control the fan speeds (odd), what you have linked to can work if you can put up with the really bright LED's.

I've not used Speedfan as MOD points out, but it's a pretty common program which I'm sure works great.

I use PC Probe II since it came with my ASUS mobo.http://www.techspot.com/downlo....html

*edit*another thing you can do, on the cheap, is to wire up your fans for less than 12v. You can use resistors or different wires from an extra molex connector. It could be done for just a few bucks, but the fan speed will be stuck where it's at, non-adjustable.

[qat727]

Well, I sort of figured the cheapest way to control the speed would be to just wire in a rheostat and be done with it.

The main question is whether or not I need to monitor the temperature if I do that, and if I do, what is the cheapest way to monitor it. I took a look over the SpeedFan stuff and it's confusing at first glance, so I think I'll give it a closer read to see if I can understand what it's supposed to do.

[240Knightrider]

have you checked your bios to make sure fan control was enabled?