UEFI BIOS not showing al fans?

likedxm

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I have an Asus Sabertooth 990FX R2.0 motherboard and I have 3 fans plugged into the board, 2 fans in a splitter and 1 in it's own slot, I also have a corsair H100i liquid CPU cooler plugged into it's own slot + 2 fans plugged into their own slots on the board, when I go into UEFI BIOS only 3 of these fans are actually displayed there? Also one of the fans keeps jumping from 1200rpm to 65000rpm and back again, can anyone explain this? I have the latest BIOS for this motherboard & all of the fans are working.
 
Solution

This depends on what fans are able to report to the board. Your board should be able to report upto 6 fans total(at least from what I see on the Newegg images.).


The adapter with 2 x 4 pins on one side and a motherboard connection of the other will only let one fan speed show up. So not matter what, you will only see one of the 2 fans in this...
1200 - 6500 sounds like a bug. It most likely it is a fan defect. You can try to plug another fan into that header to see what it says.

I do have to ask about the fan splitter.

Is it the one that plugs into the H100i? If so, the H100i will report speeds in its own software and not the bios. The bios can see the H100i pump speed only.

If it is another fan splitter, please ensure that one plug has 4 wires and the other has 3, if not, 2 sets of fan speeds are being sent to the board. This can cause misreads for sure. To be 100% sure, you should plug a since fan into that slot to make sure the board is not the issue. I can post an image if you want to see what I am talking about, but it is generally the yellow wire(third one next to black and red). Many fan splitters come setup wrong, I always just remove the extra wire and its pin to avoid issues.

With any of these fan splitters(the Corsair one is not actually a splitter), you can only see the speed of ONE fan since the header is made for a single fan.

It looks like things are working right as you see one of the fans on the splitter, one other fan and the corsair pump(that should also be connected to a SATA power cable to power it.).

I hope this clears things up a bit.
 

likedxm

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The fan is brand new but I will try another and see if it works, it just seems weird that some fans are shown and other are not?

I am using a different fan splitter, it has two 4 pins on one side and plugs into all 4 pins on the MB.
The splitter I got with the H100i was completely wrong and was not a fan splitter at all, I have never seen the connectors before that it has.

I can't see the wires as they are shielded by black rubber on the splitter?

The two fans on the H100i are in their own connectors as I did not receive the correct splitter for it, 2 of my case fans are in the splitter, yet a single case fan plugged into it's own individual slot is the fan giving me readings from 1200rpm to 6500.
 

This depends on what fans are able to report to the board. Your board should be able to report upto 6 fans total(at least from what I see on the Newegg images.).


The adapter with 2 x 4 pins on one side and a motherboard connection of the other will only let one fan speed show up. So not matter what, you will only see one of the 2 fans in this configuration.
The corsair cable should have a nearly flat plug on one side and 2 fan plugs on the other. This unit plugs into the actual pump unit to regulate speeds. The speeds can be adjusted within the Corsair Link software in Windows.

Alternatively you can use the CPU_FAN and CPU_OPT fan headers that are next to one another to control both cpu fans on the H80i

Lets just hope it is setup right, it will not damage anything even when setup wrong, just can cause some speed reporting issues

I would try the single fan on other headers to see if it does the same thing. If it does, it is a fan issue.
 
Solution

likedxm

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I'm going to try a few things over the next couple days, will probably post again if I can't figure it out, thanks.