z800 fan speed and temperature sensor

[DGroves]

strange, i (and other people ) have no problems finding it

https://h30434.www3.hp.com/t5/Business-PCs-Workstations-and-Point-of-Sale-Systems/Replacing-z820-rea...

you only need one, controller board to do this conversion you will need

1 fan PWM controller board

2  fan PWM extension cables (used to allow fans to connect to controller board) i recomend 4 18in extension cables

3  two replacement PWM rear case fans   92mm x 25mm

4 two replacement PWM memory cooler fans   80 x 25 mm

remove the  existing HP rear fans, and the  memory fans, replace with the new PWM fans w/extender pwr cables and connect to controller board which should be mounted near the front of the case

to fix the motherboard bios fan error you can splice the PWM  tach line from each new fan  onto the motherboards fan PWM tach  pin  #3  remember the  two rear case and memory fans  combine the tach lines into one (ie- both fans  use same signal)    for the 2 front fans, you can again run a tach line from the new fan to the  motherboard/new fan controller tach pin

as long as the motherboard sees a valid tach signal, the bios will not give a error

if you want to instead place voltage limiting  fan speed resistors on each fan's 12volt line

they should be 5-10 watt 5% tolerence 45 or 50 ohms

[Jogging]

I

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@DGroveswrote:

strange, i (and other people ) have no problems finding it

...

Thanks very Much, Any dubt of mine seems to be cleared.

Grazie Mille  D.Groves

Gabriele

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[Aussie_Pezza]

I have ordered 5 mentioned transistors and a few 1k ohm resistors, and am going to make the temp sensor myself as I can't justify paying $50 plus for a cable I don't need.

Can I confirm the wiring for the transistor will go like this?

Base - goes to pin 11 via a 1k ohm resister 

Collector - goes to pin 12.

Emitter - unused

Thank you for your knowledge much appreciated.

[DGroves]

looks good, as a quick test i would just place the  2 leads into the header that mates to the motherboard and see if the fans now ramp down in speed

if not you can do what i did (sensor circuit on mb is bad) i used two 52 ohm  1 watt 4 pin fan speed reducers for the front two fans, and two 5 watt 52 ohm 1% tolerence resistors spliced into the 12 volt lines of the memory and rear fan lines you need 5 watt resistors because these each have 2two fans, so the power draw is more than a single fan