PowerMac G5 fans going crazy

[Mark Millard]

> On 2021-Feb-17, at 05:17, Jason Bacon <bacon4000 at gmail.com> wrote:
> 
> 
> It's a known issue - search the archives of this list.  I think someone mentioned that it's been fixed in 13-BETA2,

No fixes for the mis-matched times across cpus issues have been
committed to main or stable/13 . Sleeping threads can still sleep
way too long.

> but my PowerMac has problems with the DVD drive and thumbs its nose at all my current USB sticks ( had an old LG 2GB that worked, but it died ), so I can't verify right now.
> 
> Also, I suggest to anyone with a liquid-cooled PowerMac to put some sort of deflector over the power supply, assuming the PS is at the bottom of the case like the models I managed in the past. The CPU cooler is likely to leak at some point and drip antifreeze into the PS.  Loud noise, lots of yellow smoke.  It's exciting...
> 
> Best,
> 
>     JB
> 
> On 2/16/21 8:49 PM, Julio Merino wrote:
>> Hi,
>> 
>> I have this liquid-cooled dual G5 PowerMac sitting in my cold garage. The
>> machine runs fine for a while and can even do a buildworld in silence...
>> but sometimes, pretty much at random, decides to spin up its fans to the
>> maximum. The machine is pretty much idle when this happens so usage doesn't
>> explain this.
>> 
>> I haven't correlated this fully, but when the machine does this, it seems
>> to also become unresponsive. Moving the mouse on the console shows the
>> pointer moving but it eventually freezes. Except... the machine responds to
>> pings, and even to SSH. *However*, it is sluggish. SSH takes forever to
>> respond, but eventually does. Similarly, the console eventually recovers
>> too and allows input... until things become slow again. And while it's
>> responding, running "top" doesn't show anything strange, not in user CPU
>> consumption nor in sys.
>> 
>> Interestingly, running a "sysctl -a" makes the fans quiet down, maybe for a
>> long time, maybe for a couple of minutes only. See the diff below of
>> "sysctl -a" from while the fans are full-speed to right after, and notice
>> that the temperatures look just fine.
>> 
>> Any ideas about what might be happening here?
>> 
>> Thanks!
>> 
>> 
>> @@ -1,7 +1,9 @@
>> -dev.smusat.0.cpu_a1_core_current: 10
>> +device smu
>> +kern.consmute: 0
>> +dev.smusat.0.cpu_a1_core_current: 11
>>  dev.smusat.0.cpu_a0_core_current: 10
>> -dev.smusat.0.cpu_a1_diode_temp: 27.7C
>> -dev.smusat.0.cpu_a0_diode_temp: 26.5C
>> +dev.smusat.0.cpu_a1_diode_temp: 28.1C
>> +dev.smusat.0.cpu_a0_diode_temp: 26.7C
>>  dev.smusat.0.cpu_a1_vcore: 1
>>  dev.smusat.0.cpu_a0_vcore: 1
>>  dev.smusat.0.%parent: iicbus2
>> @@ -12,25 +14,25 @@
>>  dev.smusat.%parent:
>>  dev.smu.0.server_mode: 0
>>  dev.smu.0.sensors.slots_power: 16816
>> -dev.smu.0.fans.expansion_slots_intake.rpm: 4487
>> +dev.smu.0.fans.expansion_slots_intake.rpm: 1572
>>  dev.smu.0.fans.expansion_slots_intake.maxrpm: 4500
>>  dev.smu.0.fans.expansion_slots_intake.minrpm: 1560
>> -dev.smu.0.fans.cpu_b_exhaust.rpm: 3168
>> +dev.smu.0.fans.cpu_b_exhaust.rpm: 551
>>  dev.smu.0.fans.cpu_b_exhaust.maxrpm: 3200
>>  dev.smu.0.fans.cpu_b_exhaust.minrpm: 500
>> -dev.smu.0.fans.cpu_a_exhaust.rpm: 3031
>> +dev.smu.0.fans.cpu_a_exhaust.rpm: 548
>>  dev.smu.0.fans.cpu_a_exhaust.maxrpm: 3200
>>  dev.smu.0.fans.cpu_a_exhaust.minrpm: 500
>> -dev.smu.0.fans.cpu_b_intake.rpm: 3045
>> +dev.smu.0.fans.cpu_b_intake.rpm: 534
>>  dev.smu.0.fans.cpu_b_intake.maxrpm: 3200
>>  dev.smu.0.fans.cpu_b_intake.minrpm: 485
>> -dev.smu.0.fans.cpu_a_intake.rpm: 3173
>> +dev.smu.0.fans.cpu_a_intake.rpm: 538
>>  dev.smu.0.fans.cpu_a_intake.maxrpm: 3200
>>  dev.smu.0.fans.cpu_a_intake.minrpm: 485
>> -dev.smu.0.fans.backside.rpm: 2851
>> +dev.smu.0.fans.backside.rpm: 1174
>>  dev.smu.0.fans.backside.maxrpm: 3000
>>  dev.smu.0.fans.backside.minrpm: 1100
>> -dev.smu.0.fans.drive_bay_a_intake.rpm: 3792
>> +dev.smu.0.fans.drive_bay_a_intake.rpm: 1011
>>  dev.smu.0.fans.drive_bay_a_intake.maxrpm: 4000
>>  dev.smu.0.fans.drive_bay_a_intake.minrpm: 1000
>>  dev.smu.0.%parent: ofwbus0
>> 
> 


===
Mark Millard
marklmi at yahoo.com
( dsl-only.net went
away in early 2018-Mar)