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Raghid-1992
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z820 workstation rear fans on highest speed all the time

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Z820 Workstation
Microsoft Windows 10 (64-bit)

My z820 workstation since I bought in 2012 the fans are so loud and on highest speed all the time from the second I press the power til I shot down, I tried to change the os from win7 to win10 and still the same....
So I tried to update the Bios from version 01.02 to 01.20 to 3.94 and still the same....
Tried to reset the Bios sitting to the default but nothing has changed
Tried another power cable, another power supply, even I changed the rear fans from another z820 workstation (I have another workstation but it is totally normal) and still the same....

What can I do to make my workstation like other normal workstations?
please help... my ears are dying

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DGroves
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search this forum for "z820 fan speed at max" and you will see several previous posts on this subject

as i posted, the official fix is to replace the z820 power button/harness which also contains the ambient tempture sensor

 

when the sensor fails, the case fans will default to full speed, replacing the cable harness will usually fix the fan speed

 

if you have a local computer shop, the existing cable can have it's sensor fixed by opening up the black covering where the NPN 2n222a plastic TO-5 transistor resides ,  replacing it, making sure it's wired up exactly the same

 

the wiring for the transistor found in the power button cable


Collector and Base leads connected together (pin 11)

Emitter (pin 12)

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Raghid-1992
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just to make sure...
do you mean this one? does it has a number or anything legit?
s-l1600.jpg

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DGroves
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if this is picture is the z820 cable yep,.....

(note the z800 pwr button looks almost the same, but is using a different wiring pinout and number of pins)

 

look at the speaker, trace the wiring back towards the black cable end, right at that end in the picture note the small raised bump,....that's the npn transistor used for the ambient temperature sensor

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