yellow wire

[orange]

Is it possible to somehow use third (yellow) wire on fan so that Amiga might know RPM? or at least just to add some LED that would light up if fan is (not) rotating at all?
 :-)

[Tahoe]

No, but depending on the model of Amiga you have you could buy something like this:
http://www.macpower.com.tw/products/peripherals/dd/tc_beige
Actually most baybus type fan controllers work with the Amiga as they are system independant.

(I have this DigiDoc 5 in my PC, it's basically a small PCB which you could hack in any Amiga if you are handy enough)

[Amiga4k]

I sent you an email on a company that sells kits.
There might be other options out there.

** Kids -- do not try this un-supervised ***
Standard 12 volt CPU fan with low revs.
Hook up to 12vdc and AMP meter, turn  on supply.
Running fan: Supply 10.5vdc and AMPS 0.16
Blades stopped: Supply 10.0vdc and AMPS 0.20

[orange]

I bought 'Spire CF203-NEB DigiPanel Silver' for my towered A4000D. its a bit pricey (38e) but works great. It has only 3 sensors and fan controls compared to 8 that yours have, and doesn't have voltage meter, but its better looking  :-) .

I have put one sensor on CPU and other beneath power supply(?) (fan #1 is on CPU and fan #2 is the big one in PSU). not sure where I should put #3 as I only got two fans.

I disconnected HDD fan in order to turn down noise.

I like this thing so much that I'm plannig on buying another one for my desktop A4000D.  It would be perfect for filling the gap that cdrom left. (dont have that plastic cover  :-( )
The only problem is that those things are so HARD to find here, and byuing over Internet is risky because of customs . :-(

@Amiga4k
I didn't receive your mail probably because of filters, please send me PM. I'm not sure if I understood rest of your message, are you surprised that stopped fan uses more current?