3-Pin Fan Header Pin Order

[Iain Barker]

Chris Meadors wrote:
> Two questions.  Do I have the wires in the right order?  (I'd think so,
> else the fan wouldn't be spinning).  Can a fan be too fast, or are the
> Alphas real picky about the RPM signal?

I had the same problems with fans on AS4100 CPU's. I was trying to use generic Delta AFB0612HA fans to replace HP AFB0612HA (i.e. same part code)

I tried ten generic fans on three CPU cards with all possible pin orderings. None worked. Replacing the fan with an HP original part worked fine though on all three cards.

The delta is spec'd at 12v 4200 to 5000RPM. Don't have the spec details of the HP part but it seems the RPM output expected by the HP tach module may be a different rate???

>From memory, if you look closely at the part codes there is a suffix -120 or -40 or something which may explain the difference in RPM speeds.  I've not seen the 'HP version' available anywhere other than direct from HP support sales.