Manual fan control on iBook G4?

[Alexey Dokuchaev]

Hi there,

I've digged out that old pity iBook G4 of mine (should be something like
PowerBook6,5 I guess) that had been hanging under Tiger within few minutes
after boot and installed FreeBSD on it.  Surprisingly, it works fine under
it. :)

I'm suspecting either a faulty harddrive, or non-working fan.  So far no
matter what heavy port I build, fan does not kick it.  Does FreeBSD support
fan control on this baby?  How can I manually engage it to see if it works?
(I've tested that power line has +5V, but don't know how can I PWM control
it from command line.  Is it PWM, in fact? -- just guessing since there are
four wires coming into it.)

Another weird thing: CPU frequency per dmesg(8) is strangely low:

  $ grep cpu0 /var/run/dmesg.boot
  cpu0: Motorola PowerPC 7447A revision 1.1, 535.22 MHz
  cpu0: Features 9c000000<PPC32,ALTIVEC,FPU,MMU>

while per various websites, 7447A CPU on it should clock at at least 1GHz.

Any clues?  How can I read Mac model from NVRAM (akin to what Mac OS X
provides via `hw.model' sysctl, or something like that)?  Thanks.

./danfe