HELP!! Dell AHF-2DC-2100W fan speed control.. LOUD

novak@gekkoscience

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Quote from: scyth33 on April 06, 2015, 12:00:43 AM

Quote from: novak@gekkoscience on April 05, 2015, 02:54:52 PM

Quote from: sidehack on April 05, 2015, 09:31:54 AM

I think we've got one of these at the shop. Novak spent more time playing with it, I'll see if he's got any notes on the thing.

I didn't really look for fan control, I pretty much just switched it on and played with voltage adjust.

B2 to 5v via potentiometer = voltage increase
C4 to 5v via potentiometer = voltage increase
C2 to 5v = voltage increase

Here's the pinout reference I found and everything I checked on it seems to be correct- but it has no fan speed control.

http://static.rcgroups.net/forums/attachments/3/1/3/5/4/3/a4644398-12-Dell%20Poweredge%202100w%20pinout.jpg?d=1329627059

I can double check but for some reason I was thinking the fan went on full speed when the supply is first powered on but slowed after a second or so (at basically zero load). If that's the case we might have slightly different supplies or possibly yours has a bad temperature sensor or something.

--
novak

does adjusting the voltage affect the fan? my fan turns down after startup too but not silent

No, adjusting the voltage has no effect (again, at pretty much zero load so I assume it is temperature driven). Mine is also not silent.

--
novak

scyth33

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Activity: 99

Merit: 10

Quote from: novak@gekkoscience on April 05, 2015, 02:54:52 PM

Quote from: sidehack on April 05, 2015, 09:31:54 AM

I think we've got one of these at the shop. Novak spent more time playing with it, I'll see if he's got any notes on the thing.

I didn't really look for fan control, I pretty much just switched it on and played with voltage adjust.

B2 to 5v via potentiometer = voltage increase
C4 to 5v via potentiometer = voltage increase
C2 to 5v = voltage increase

Here's the pinout reference I found and everything I checked on it seems to be correct- but it has no fan speed control.

http://static.rcgroups.net/forums/attachments/3/1/3/5/4/3/a4644398-12-Dell%20Poweredge%202100w%20pinout.jpg?d=1329627059

I can double check but for some reason I was thinking the fan went on full speed when the supply is first powered on but slowed after a second or so (at basically zero load). If that's the case we might have slightly different supplies or possibly yours has a bad temperature sensor or something.

--
novak

does adjusting the voltage affect the fan? my fan turns down after startup too but not silent

novak@gekkoscience

full member

Activity: 173

Merit: 100

Quote from: sidehack on April 05, 2015, 09:31:54 AM

I think we've got one of these at the shop. Novak spent more time playing with it, I'll see if he's got any notes on the thing.

I didn't really look for fan control, I pretty much just switched it on and played with voltage adjust.

B2 to 5v via potentiometer = voltage increase
C4 to 5v via potentiometer = voltage increase
C2 to 5v = voltage increase

Here's the pinout reference I found and everything I checked on it seems to be correct- but it has no fan speed control.

http://static.rcgroups.net/forums/attachments/3/1/3/5/4/3/a4644398-12-Dell%20Poweredge%202100w%20pinout.jpg?d=1329627059

I can double check but for some reason I was thinking the fan went on full speed when the supply is first powered on but slowed after a second or so (at basically zero load). If that's the case we might have slightly different supplies or possibly yours has a bad temperature sensor or something.

--
novak

scyth33

member

Activity: 99

Merit: 10

Quote from: Acid Alchamy on April 05, 2015, 12:54:14 PM

Simple...Open up PSU and add a 1/2 Resistor at whatever Ohms to the power cable leading to the fans. Ive done this to a few server PSU's just to make them more quiet.

Enjoy,

that's my temp solution. but I'm afraid the psu would overheat. sometimes the psu won't turn on if the fan is spinning too slow, any solutions to that?

Acid Alchamy

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The One, The Only

Simple...Open up PSU and add a 1/2 Resistor at whatever Ohms to the power cable leading to the fans. Ive done this to a few server PSU's just to make them more quiet.

Enjoy,

Subw

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Activity: 672

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Quote from: klondike_bar on April 05, 2015, 08:30:17 AM

pretty sure its internally controlled based on load and temperature sensors.

nope, it is constant speed regardless of load or temperature

scyth33

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Quote from: sidehack on April 05, 2015, 09:31:54 AM

I think we've got one of these at the shop. Novak spent more time playing with it, I'll see if he's got any notes on the thing.

sure! thank you. this psu is very loud....

sidehack

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I think we've got one of these at the shop. Novak spent more time playing with it, I'll see if he's got any notes on the thing.

klondike_bar

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ASIC Wannabe

pretty sure its internally controlled based on load and temperature sensors.

IME with server PSUs, anything over 40% load gets loud, and anything over 70% load gets outrageously loud. at 90+ load you absolutely need a datacenter due to noise

philipma1957

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Quote from: scyth33 on April 05, 2015, 07:44:08 AM

Hi, i've got the dell 2100w psu. its insanely loud. does anyone know how to manually control the speed of the fan?

maybe sidehack? send him a pm

scyth33

member

Activity: 99

Merit: 10

Hi, i've got the dell 2100w psu. its insanely loud. does anyone know how to manually control the speed of the fan?

Topic: HELP!! Dell AHF-2DC-2100W fan speed control.. LOUD (Read 2815 times)