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RPM fan monitoring problem

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Kent

Member
Joined
Jan 4, 2001
I just installed a Mechatronics 53cfm fan. The fan has been pre-wired to get it's power from your power supply using a standard 4 pin molex connector - BUT - it also has a three pin connector wired in so that it can still report fan speed information back to your motherboard. The problem is that upon installing the fan my bios (Abit KR7A-133R) reads N/A for the fan speed. I checked and the fan is running. Oh, sometimes for a split second bios reads the fan speed, but then reads N/A after that. Is the plug bad? Any ohter ideas? I really want to monitor the speed because the bios has the option to Shutdown if cpu fan fails, which would come in handy!!! :) Thanks, Kent :)
 
Does the fan's molex connector run to the yellow and black wires, or to the red and yellow wires?
 
Yellow and Black. Then the 3-pin plug(White colored wire only) runs to the MoBo header.
 
Do you have another 3 wire fan (like a case fan) to try in this plugin? Leave the cpu fan plugged into it's power supply, but plug the second fan into the #1 fan header. Read the manual for this, Abit doesn't put them in the obvious postion, my KT7A has them reversed. If you do get a good reading, then the cpu fan is to blame. You can check in the plugin to make sure there's nothing wrong to make it contact badly like loose wires or something in the plug hole. You could also try cleaning the header pins with a swab and some alcohol.

If you still don't get a good reading with the second fan, then it's either the motherboard or the drivers/bios. In that case try a driver update, then a bios update, then Abit customer support (or reseller).

Good luck to ya man!
 
I just plugged a Glaciator II into the MoBo header and it read the rpm's. I RMA'd the first fan and just received the second one, which it does not give a rpm reading either. So, this tells me the fan1 MoBo header works fine. So, why would the fan not give a rpm reading? Anyone??? Thanks, Kent :)
 
Im having the same problem with a 3pin Enermax fan I just got =(. My original 3pin worked fine as far as reporting rpm, this one does not.
 
If that fan spins below 2600 rpm or higher than 5000 rpm ( I think these are the numbers) then the MB will read N/A... Got the same MB and per docs thats what it says... Sounds like this is your prob ... Check the rpms your fan spins at and that might be your prob ... Good Luck...
 
Hey vtec96, Where did you find that info? I've looked and can't locate it. Thanks, Kent :)
 
I checked the Glaciator II again and it runs at 5,4xx rpm. I wonder if the Mechatronics fan doesn't have the rpm sensor in it? This has got me! ???
 
It looks like vtec96 is right I have the kr7a-133 and don't get any readings from my fans that I have hooked up to header 1 or 2 in the bios but in MBM5 I get readings off of them. The fans that I have are cheapos that need to be replaced but one is reading just a little below 2000rpm and the other pos is reading around 5300 when it runs!:mad:
 
I checked and the Mechatronics runs at 4,2xx rpm. So, it runs about 1,200 rpm slower than the Glaciator. I think it maybe how the Mechatronics is wired. Meaning the KR7A-133 doesn't like it. I'm going to E-mail Abit. Thanks, Kent :)
 
Kent said:
Hey vtec96, Where did you find that info? I've looked and can't locate it. Thanks, Kent :)
Ok Finally I think I found it....It looks like it can read up to 7000 according to this link, but I thought I read around 5000 somewhere else??? Anyway this is directly from Abit. Also check that all your wires are hooked up like the recommend...Your question is answered Here Good Luck ...
 
Here is what the link stated.

1. Please refer to user's manual section 2-4, page 2-9. The fan1 header is for CPU fan, and fan2 header for chassis fan. If "current CPUFAN speed" reports NA in PC Health page, but "chassis FAN speed" is with reading, it may indicate that CPU fan is wrongfully connected to fan2 header.

2. If the fan speed is too high or too low, higher than 7000 RPM or lower than 2600 RPM, BIOS code may ignore it and report "NA".

3. The CPU fan or chassis fan should be three wires, with signal wire for fan speed detection; otherwise PC Health will report "NA".


So, looks like line #3 is the problem. That's why it read the Glaciator II. It has a standard 3-pin plug, unlike the Mechatronics which has the standard 4-pin molex for power and the 3-pin wired for rpm monitoring. I'm going to install MBM5, so it looks like mustangman has figured that out. Diggrr might also be right. Maybe a bios update??? Thanks a lots guys/gals. It's good to see how we can find an answer working together. Kent :)
 
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On my mobo it works.... Strange!

I have a Shuttle AK35GTR

Fan incompatabilities! Now that's rich!

(Not saying it's false, just funny)
 
Mechatronics works fine on K7S5A on both headers.

Doesn't the comment about
3. The CPU fan or chassis fan should be three wires, with signal wire for fan speed detection; otherwise PC Health will report "NA".
refer to two wire fans that don't have rpm monitoring such as Panaflos?

My only problem is I'd like them to also work when 7volted but the rpm drop tto low to be reported by MBM
 
Kent said:
So, looks like line #3 is the problem. That's why it read the Glaciator II. It has a standard 3-pin plug, unlike the Mechatronics which has the standard 4-pin molex for power and the 3-pin wired for rpm monitoring. I'm going to install MBM5, so it looks like mustangman has figured that out. Diggrr might also be right. Maybe a bios update??? Thanks a lots guys/gals. It's good to see how we can find an answer working together. Kent :)

kent,

did installing MBM allow you to monitor the fan that wasn't showing up in the bios?

i have a asus a7v333 and i'm trying to run a panaflo fba08a12h 80mm fan on it with a 3 wire tail. i'm getting the same problem, no rpm in the bios. i want to keep the fan, so if MBM will let me see it, great. (i don't really care about the fan speed while in the bios anyway. not really that cpu intensive. :)

i know it's pretty new, but anyone else have any trouble monitoring fans on this motherboard? i tried several other brands of fans and they are read just fine.

what do people think of the panaflos generally? this is my first and i'm hoping my rpm problem is an exception to the rule.
 
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