I downloaded the Mac OS X 10.5.6 update the day after it was
released, which for me involves a 24 mile round trip to the library,
whose WiFi connection is slow - but still a lot faster than the 26,400
bps dialup connection I get at home. Anyway, once I had it in hand, I
continued to hold off running the installer, my hesitation due to an
extraordinarily large volume of post-upgrade trouble reports I'd been
reading on various forums.
Hot Running
However, on New Year's Eve, my usually dependable, predictable,
solid-as-a-rock trouble-free 1.33 GHz PowerBook G4
started running hot, with its cooling fans cutting in and out on what
settled into a roughly 3-minutes-on, 30-seconds-off cycle. I've found
that the PowerBook does tend to run a bit hotter after a fair bit of
time elapses since the last system reboot, and certain web pages can
also have content that seems to stress the processor. In the latter
instance, closing the page, the browser window, or quitting and
restarting the browser usually restores cooler running, as does
rebooting the computer.
This time, however, none of the usual nostrums worked, and I found
that the freshly rebooted system was still cycling between processor
temperatures of 58.5°C (the cooling fan cut-in threshold) and
55°C (the temperature where the fan goes silent again). This
machine normally runs in the high 40°s and low 50°s under light
to moderate processor loads, with the fans mercifully silent.
Something had obviously changed.
I decided to run the
OnyX Repair Permissions, cron scripts, and cache dump system
maintenance routines and rebooted hopefully, but no joy. The fans began
howling almost before the boot cycle had completed.
It's the OS
For purposes of diagnostic comparison, I next tried booting into
OS X 10.4.11, which I keep installed on another hard drive
partition, and the temperature readout stabilized at 49° to
50° - well below the fan activity threshold.
It seemed this was not a hardware problem.
Back in OS X 10.5.5, I was still getting overheating. I figured I
might as well try updating to 10.5.6, not a project was really
enthusiastic about starting at 1:00 a.m., which it was at the time. But
I've always had pretty good
luck with Mac OS X updates, there was the fresh system
maintenance, and I wanted to fix the problem, so I resolved to go
ahead.
Update Problems
The update installation ran normally, taking about 15 minutes and
delivering the welcome "The Software Has Been Successfully Installed"
message, but that was where the usual routine petered out. On the
obligatory restart, I got a gray screen for about half an hour,
accompanied by a lot of hard disk activity interspersed with periods of
silence that left me wondering if the machine had hung. Finally, a blue
screen appeared, followed by a second reboot and the gray screen
again.
I finally lost patience and hit Cmd-Ctrl-power, forcing the computer
to reboot, then holding down the Shift key to select Safe Boot Mode.
Anther long wait, and my finger holding down the key was tired by the
time the PowerBook did boot at last. The Desktop reappeared, but it was
again accompanied by the caterwauling fans.
At that point I tried one more reboot, a normal one this time, and
mirabile dictu, the machine settled down to running at 47°
to 48° and stayed in that range while I sent a few emails and
battened things down for the night, it by that time being 3:30 a.m. I
went to bed optimistic that problem had been licked.
Not.
About midday on January 2nd, we had a short power outage while
utility crews cleared some fallen trees off a neighbor's power lines,
residue from a major snow and wind storm that battered us for about 30
hours on New Year's Day. The power going out and coming back on usually
makes the sleeping PowerBook wake up, and so it did this time, only I
was out and didn't notice it until several hours later, when I walked
into my office and found the machine running with the fans screaming
away - nothing changed and the same two or three programs open as I had
left it the night before. Most disappointing.
Maybe It's Not the OS
I keep a cloned copy of my hard drive and boot system on an external
FireWire drive, so I booted up from that system (OS X 10.5.5). I
was delighted to observe that the PowerBook settled down running at
47° to 50° under light to medium processor loads, holding that
temperature range through a several hour work session. It was even a
bit more lively than usual, since the external drive is a 7200 RPM unit
as opposed to the 80 GB 4200 RPM drive in the laptop.
However, there was still something evidently amiss with the Leopard
install on the internal hard drive, and I determined that I was
probably going to have to do a clean system install in order to
eliminate whatever was causing the overheating, something it hadn't had
since I purchased the computer just shy of three years ago, beginning
with OS X 10.4.7 or so and just updating and upgrading that
original installation through every version since.
I run dozens of applications, probably more than 100 over the course
of a year, many of them beta or even alpha builds, so the possibility
of some sort of corruption was not implausible. In the meantime, the
external FireWire drive was doing a fine job as a stand-in,
underscoring once again how wrongheaded it was of Apple to drop
FireWire support from the new Unibody MacBook.
On Saturday evening, I tackled the system reinstall. I dragged all
the System related files from my hard drive's main boot partition to
the Trash and flushed, which took quite a while, as there were well
over 200,000 (mostly small) files to dispense with.
Backup Serenity
With a recently cloned system on one external hard drive and an
up-to-date Time Machine backup on another, I had no anxiety about
trashing the old system.
At that point I thought it might be a good idea to defragment the
data still left on the boot volume (mostly applications and data
archives), so I started up Drive Genius
2 and commenced a defrag run, which crapped out with the process
about half complete. A message appeared saying a directory problem or
somesuch was preventing the defragmentation from completing and
suggesting I run the Drive Genius Repair module. That I did, and it
returned an "appears to be OK" clean bill of health.
Back to the defrag module - but the process stalled again.
All right, perhaps it was time for DiskWarrior. I
popped in the DiskWarrior 4 CD and booted from it, something I don't do
as often as I would like, since the bootup takes 10 to 15 minutes -
longer than the directory rebuild process itself, which in this
instance ran smoothly. DiskWarrior did find some damaged directory
files, as it usually does, but nothing major, and it was able to repair
them when it replaced the directory with a fresh new one. While I had
DW up and running, I took the opportunity to rebuild the disk
directories on the PowerBook's other two partitions as well.
A reboot, and back into Drive Genius 2, only to discover that the
program not could not mount that partition at all.
Reinstall Leopard
I decided to give up on the defrag and just go ahead with installing
OS X 10.5 from scratch, opting for an almost-but-not-quite clean
install, deciding to save myself a lot of configuration tedium and
ennui by importing the User and settings files from the cloned system
on the external FireWire drive, which seemed quite healthy.
The installer on the Leopard DVD did its stuff without drama, after
which I ran the 10.5.5 Combo updater. Experimenting a bit after the
reboots, I found that the heat issue was somewhat improved, but the
PowerBook was still running hotter than it had customarily done in the
past.
Might as well go for it and run the OS 10.5.6 updater - and this
time it worked a lot more quickly and smoothly than on my first
adventure described above. It booted with reasonable dispatch with no
gray or blue screen stalls.
At the end of several days and a couple of very late nights, I'm
happy to tentatively and cautiously report success at last. As I put
the finishing touches on this column, the PowerBook running OS X
10.5.6 from its own hard drive is six hours and 40 minutes into a work
session, and the cooling fan has only cut in once in that time during a
flurry of email and page loading throughput via the internal dialup
modem, which does tend to make the machine run hotter when in use.
However, for the most part the Temperature Monitor readout has been
ranging from a low of 43.5° to 52° - well short of the
58.5° fan cut-in point, and 10.5.6 has been a smooth performer so
far.
Hoping it stays that way.
