High-speed 4-pin PWM 120mm case fan

ldoodle

Limp Gawd
Joined
Jun 29, 2011
Messages
172
Hi,

The motherboard from an HP ML110 G7 server has hard-coded some sort of fan RPM requirement and if it doesn't meet it, it reports an error then powers off. I don't know and can't find what the minimum RPM is.

The original 80mm fan (Delta PFB0812GHE) is rated at 6100 RPM, which at full speed is way too noisy for a SOHO environment. I tried Noctua's NF-F12 industrial 3000 RPM fan and even this isn't 'good' enough, even without PWM wire connected to force it to spin at full speed. It's crazy because the original case has this 80mm fan at the front, a 92mm fan on the CPU and 92mm fan at the rear. New case has 3x 5-in-3 drive caddies which all have fans, so overall provides much better cooling even without the 80mm fan attached!

I've transplanted the guts of this server in to a new (much bigger) case which only has 120mm mounting holes.

Anyone know a fan with high enough speed that this board might accept?

Thanks
 
Maybe try one of these 120mm fans, if the header can do 40 watts,
this was the rear fan on my Intel chassis and ran off the motherboard.
IMG_0864.JPG
 
Thanks zepher - the original 80mm fan is rated at 10.2W so I doubt the HP board can do 4X that on the header and it's unlikely HP will divulge what it can do.

What will happen if it can't do 40W - just not spin or more severe damage?
 
Thanks catscratch. I don't think max 2400 RPM is enough. It needs to be more than that minimum!
 
Thanks zepher - the original 80mm fan is rated at 10.2W so I doubt the HP board can do 4X that on the header and it's unlikely HP will divulge what it can do.

What will happen if it can't do 40W - just not spin or more severe damage?

I have no idea what would happen. It may fry the header on the motherboard if the fan pulls more than the header can supply. I don't have any junk machines lying around otherwise I would hook it and see what it does.
That fan sounds like a leaf blower when the motherboard cycles the fans to 100% during POST.

here is a video showing amps and volts as he turns up the voltage,



specs,
http://www.nidecpg.com/fanpdfs/va450dcf.pdf
 
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Thanks catscratch. I don't think max 2400 RPM is enough. It needs to be more than that minimum!

120mm fans that spin more than 2000rpm are not common. I have a Nidec GentleTyphoon on my H60i that spins at 2150 max and I thought that was fast. Great fan btw, so quiet and moves so much air! I found a Scythe 120 that spins at 3K but it's not PWM. You might just have to find a way of fooling the motherboard into thinking the fan spins that fast.
 
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I have no idea what would happen. It may fry the header on the motherboard if the fan pulls more than the header can supply. I don't have any junk machines lying around otherwise I would hook it and see what it does.
That fan sounds like a leaf blower when the motherboard cycles the fans to 100% during POST.

here is a video showing amps and volts as he turns up the voltage,



specs,
http://www.nidecpg.com/fanpdfs/va450dcf.pdf


That sounds like it's gonna take off!
 
No matter what size fan you use, at that rpm its going to be very noisy. Quite a ridiculous setup!
The only way round this is to use a square wave frequency doubler/tripler circuit to multiply up the PWM signal coming from the fan, or send a fixed frequency to match what is needed.
Either that or ditch it.

Are you sure there is no way to configure lower rpm or remove the speed detect in the bios?
I cant imagine it would insist the fan run full pelt all the time.
You could try resetting the cmos, it might default lower.
 
No matter what size fan you use, at that rpm its going to be very noisy. Quite a ridiculous setup!
The only way round this is to use a square wave frequency doubler/tripler circuit to multiply up the PWM signal coming from the fan, or send a fixed frequency to match what is needed.
Either that or ditch it.

Are you sure there is no way to configure lower rpm or remove the speed detect in the bios?
I cant imagine it would insist the fan run full pelt all the time.
You could try resetting the cmos, it might default lower.

probably just needs to ramp the fan to 100% during post to make sure the fan(s) are all working, if there is an issue, it just powers down.
 
probably just needs to ramp the fan to 100% during post to make sure the fan(s) are all working, if there is an issue, it just powers down.
Yeah I figured that after posting but couldnt be asked to add it because the fixes are the same.
 
Yeah I know - I am hoping there is an acceptable range at which it will POST ok, with the bottom of the range being far away from 6100!

From my testing with the original fans, it doesn't spin them at 100% on power on so that suggests it's maybe looking for a percentage of the original fans RPM (as in OP, it's 6100) on power on, or even that the fan has a minimum RPM of something stupidly high - and if so it's more than 3000 RPM otherwise it would have been happy with the Noctua fans connected without the PWM wire.

There's nothing in the BIOS re: cooling other than choosing between 'Optimal cooling' and 'Increased cooling'. It's really annoying because the cooling in this case, with the fans in the 5-in-3 drive cages is exceptionally superior to the original manufacturer case!!

I'd rather not ditch at this stage because it'd be quite an expensive system to replace, like-for-like or close to it.
 
If found someone doing the exact same thing: https://forums.overclockers.co.uk/threads/fan-advice-for-hp-ml110-g7-mobo.18432265/

The server's BMC is probably getting upset by either lower RPMs than it expects, or a lower current draw. Find the specs for the OEM fans and then try to find something that's at least a reasonable match (current draw and rpm range) in the size required.

https://www.arrow.com/en/products/pfb0812ghe/delta-electronics

Voltage Rating (V): 12
Operating Input Voltage Range (V): 7 to 13.2
Line Current (A): 0.85
Power Rating (W): 10.2
Nominal Speed (r/min): 6100

Maybe it's not (just) RPM. I can't find line current specs for the Noctua's.
 
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Is there a BMC setting on the board?
I know my Intel S2600COE had some BMC settings and I could tell it if there were fans on the any of the motherboards headers.
Maybe your board has something like that and you can tell the board there are no fans on the headers and see if it will post.
 
It has HP iLO, which is probably not dissimilar to BMC. I'll check that out.

Screenshot_20190424-150504.png
 
Well, in the BIOS I can enable or disable 'Thermal shutdown', but this doesn't affect 'wrong' fans being used as it still gave me the warning then powered off. It only seemed to stop the 'health' LED turning red!! :)

Nothing in iLO config about thermal at all.
 
Thanks ryan. That model looks to come from both ML150 G6 and ML330 G6 servers. I also found AVC DS12025B12UP024 (1.05A) which comes from both ML150 G5 and ML310 G5 servers, and looks to be 3800RPM full.

What I did try is swapping the headers around for the original 80mm and 92mm (AFC0912DF) fans and that was ok - the 80mm fan is 0.85A and the 92mm is 1.43A and 4500RPM so it looks like they haven't rigidly coded for exact amperage at each header, and hopefully exact RPMs
 
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a delta QFR1212EHE might work. its 4pin, 5000rpm, 12w and ~180cfm but is 38mm thick(dont know yours) and a bit pricey ~$30.
 
Thanks everyone.

I tried the Delta QFR1212GHE and AVC DS12025B12UP024 but both no good. The board must then be coded for exactly the characteristics of only the pre- supplied 80mm and 92mm fans.

That really only leaves me getting 120mm to 92mm adapters, but damned if I can find them that are slim!! I'm going to swap the 80mm with another identical 92mm.
 
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