[vox-tech] Demo Machine: Stopped Rear Case Fan.

Bill Broadley vox-tech@lists.lugod.org
Sat, 8 Jun 2002 01:14:49 -0700


On Fri, Jun 07, 2002 at 05:50:33PM -0400, msimons@moria.simons-clan.com wrote:
>   A while back I commented that the read case fan had failed.
> One of the things I did yesterday was to swap the front and rear case
> fans to see if the fan was operational or not.  It turns out that the
> fan is 100% operational...

I assume the old front fan that is the new rear fan didn't spin up.

>   I think the motherboard isn't suppling power to the back case fan
> connector.  I checked the motherboard manual and there is no BIOS option
> which may do a temperature based or power conservation stop of the fan
> is on.

It's likely dead, abit bp6's are famous for this, no idea what
kind of motherboard this is.

>   Another defect appears that the SMBus chips can not read the 
> CPU1 Fan speed... I connected one of the case fans (which are
> known to report RPM information) to the CPU fan connectors... and
> while they spin there is no RPM information available.

Is the cpu1 fan connector connected to a fan with 3 wires?  2 wire
fans will spin but not show rpm.

> - Someone with electrical skills want to test out the three pin 
>   fan connector to figure out what is going wrong?

I'm betting on a short.

> - Any suggestions on how to get the fan spinning? (1)

Get an adapter from the standard 4 pin power supply to whatever
the fan takes.

> - Has anyone else seen motherboards fail to spin fans like this?

Common on abit's, most often when using a higher performance (more
power hungry) fan, or when plugging/unplugging fans while
the machine is on.


-- 
Bill Broadley
Mathematics/Institute of Theoretical Dynamics
UC Davis