schizophrenic G5 ...

[Benjamin Herrenschmidt]

On Sun, 2008-12-21 at 16:11 -0800, Kevin Diggs wrote:
> Hi,
> 
> 	I have a water cooled dual 2.5 GHz G5 (Powermac7,3). It has YDL 6.0 on 
> it. Using the stock YDL 2.6.23 kernel this machine "appears" to work fine.
> 
> 	After finally getting it to boot under 2.6.27, it will shut itself off 
> if put under any significant load. And it is doing it very quickly. Like 
> within a few seconds of becoming busy. I just discovered it is spitting 
> out messages about "temperature way above maximum" (from therm_pm72.c).
> 
> 	This one has the Panasonic cooling system. I have checked behind the 
> cover and see no evidence of leaks.
> 
> 	When put under load under the stock YDL kernel, the cpu fans will speed 
> up for about 2 minutes. Then over the next minute or so they will slow 
> down almost to idle. Thereafter a whirring sound can be heard every 15 
> to 30 seconds lasting about 5 seconds. Which I am guessing is the pump? 
> The exhaust air barely gets warm?
> 
> 	Anyone have any ideas? Could the cooling system NOT be correctly 
> thermally connected to the cpus?

I have approx. the same here taking dust under the desk, I'll give it a
spin but i might have to wait a couple of days...

If mine works, then we'll have to run some more intensive debugging to
see what's going on.

Cheers,
Ben.