[SOLVED] Case fans wont start / twitch

TheRickert

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Okay so yesterday i bought 3 new pwm case fans: coolermaster mf120 halo

I daisy chained them and plugged both the pwm header and rgb header in. However only one or two fans start spinning, the third twitches and will only spinn when manualy pushed

Motherboard is asus rog x570- e gaming.

Look to me like they are not getting enough power to start (only have one header for them left) any fixes?

They do seem to start wheb fast boot is disabled, which i find weird
 
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Okay quick update! Thanks guys! Yes it was a 3 in one pack, connected with splitter and loose but nothing would work

I now bought corsair LL 120mm series 3 in one pack with fan hub and such.
I connected all 3 with a fan splitter cable and what happens? These work fine of the same header as on which the coolermaster mf120 halo didnt work

So guess the cooler master were just a bad bunch. Thanks for all the help

Phaaze88

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TheRickert

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I think you are correct regarding power.
https://www.coolermaster.com/catalog/coolers/case-fan/masterfan-mf120-halo/#specifications
The RGB rated current on just a single fan is HIGH.

You need another header - heck, you probably need an ARGB/fan hub, because chaining 2 likely isn't safe - assuming the header on the mobo is 1A.
https://www.coolermaster.com/catalog/coolers/?filter=50055/#!/Cooler Type=RGB Accessories
Okay thanks! I just got them al three working again and 5 min later only 2 are spinning and one is twitching, so you say buying a splitter will solve it probably?
 

Phaaze88

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A splitter, yeah, but I believe a hub would be better simply because they are rated for higher power than a single motherboard header, and also because I think you're still pushing it just chaining 2:
-hubs are usually rated for 3-4A and are powered by the psu usually through a SATA connection
-2 of those fans chained, at the minimum, is 1.10A - 1.60A max. We don't know how many amps the header is rated for either; manufacturers never seem to include that. It's usually 1A, but some are rated for 2A.
 

TheRickert

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A splitter, yeah, but I believe a hub would be better simply because they are rated for higher power than a single motherboard header, and also because I think you're still pushing it just chaining 2:
-hubs are usually rated for 3-4A and are powered by the psu usually through a SATA connection
-2 of those fans chained, at the minimum, is 1.10A - 1.60A max. We don't know how many amps the header is rated for either; manufacturers never seem to include that. It's usually 1A, but some are rated for 2A.
The fans itself is 1.10A or the rgb?
 

Paperdoc

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First, the fan MOTOR is rated for 0.25 A max current draw, which is not high. The specs also include what they call "Fan Safety Current" as a higher number that does NOT normally happen - it's a max limit for abnormal conditions. Threeoif these on one header is quite acceptable.

My suspicion is that you have confogured the mobo fan header they are connected to for a minimum speed which is too low, and just at the edge of what can be used. So that's works for one of the units, but is just too low for another. You should re-adjust that minimum fan setting higher so they all can start up reliably.
 
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TheRickert

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First, the fan MOTOR is rated for 0.25 A max current draw, which is not high. The specs also include what they call "Fan Safety Current" as a higher number that does NOT normally happen - it's a max limit for abnormal conditions. Threeoif these on one header is quite acceptable.

My suspicion is that you have confogured the mobo fan header they are connected to for a minimum speed which is too low, and just at the edge of what can be used. So that's works for one of the units, but is just too low for another. You should re-adjust that minimum fan setting higher so they all can start up reliably.
Thanks for the response! But even at 100% speed they wont start reliable... i think i will have to rma
 

Phaaze88

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The fan motor and LEDs are running separately.

As already mentioned by Paperdoc, the fan motor is rated for 0.25A at max rpm, which I didn't say was high. I didn't see a problem with you daisy chaining 3 of these onto a single header.
Even if the mobo header is rated for 1A, 3 of those just equals 0.75A, so that's still safe.

The ARGB LEDs are rated for 0.55A minimum, which is what I was saying was high. They can draw even more, to a max of 0.80A.
Daisy chaining multiple of these on the LED cables is what's proving to be problematic.
x2: 1.10 - 1.60A
x3: 1.65 - 2.40A
You really need a hub for the LEDs alone.
 

Fiorezy

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Corsair LL, QL, ML? Well, either way, I'm sure their LEDs don't draw as much power as the MF120 Halo...
I take that back; the QLs have like twice as many LEDs compared to the other 2.

All you likely needed was a hub for the LEDs... just curious on why you returned the halos?
Not sure why this was happening to him, I actually have 4xMF12 Halo installed in my chassis and they work just fine, ARGB is connected to the motherboard and then chained across all the 4 fans, and I got 3 intakes connected to the fan header via a fan splitter that was provided with the pack, and the 4th fan which works as the exhaust is connected to a second fan header. I had no issue as he described.
 
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Phaaze88

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Not sure why this was happening to him, I actually have 4xMF12 Halo installed in my chassis and they work just fine, ARGB is connected to the motherboard and then chained across all the 4 fans, and I got 3 intakes connected to the fan header via a fan splitter that was provided with the pack, and the 4th fan which works as the exhaust is connected to a second fan header. I had no issue as he described.
I don't know either.
I'd already figured by my 4th post that I was entirely wrong about what was going on.
The LED power rating for those Halos is high - I'm used to seeing Corsairs and Deepcools with 0.15-0.25A, but these things... wow. That's why I figured it was a power issue.
 
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TheRickert

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Okay quick update! Thanks guys! Yes it was a 3 in one pack, connected with splitter and loose but nothing would work

I now bought corsair LL 120mm series 3 in one pack with fan hub and such.
I connected all 3 with a fan splitter cable and what happens? These work fine of the same header as on which the coolermaster mf120 halo didnt work

So guess the cooler master were just a bad bunch. Thanks for all the help
 
Solution