Tony,

Couple of things. First, did you recently upgrade your system or any apps? Sometimes there can be conflicts.

Next, go to Applications > Utilities and open Console.app

You can find logs of recent activity there, it may shed light on what caused the problem.

Make sure you click the button on the top left to "Show Log List", then look specifically for CrashReporter.

What OS X are you running?

An out-of-the-blue freeze like that sounds like a RAM hardware problem to me. Did you upgrade recently?

no upgrades, version 10.5.3.

i had to do a force shutdown to get it to function again.

nothing in the logs.

it works now fine, but was rather odd....

Hi Tony - I've been on a g3 iBook since 2002. Running 10.3.9. I've had many many freezes. I've eaten spinning pizza for breakfast lunch and dinner. Usually not a big deal.

By 'force shutdown' do you mean that you had to press the off button and turn the power off?

If i try to open a 50 mg jpg or a very large pdf, i usually wind up doing a force quit of Preview, and there have been cases where I have had to completely shut down the machine. If you're running Photoshop, Adobe Illustrator, Dreamweaver, etc. all at the same time, then even with your newer more powerful system, your bound to freeze every once in a while.

If you actually had to turn the computer off to escape, well that's a little rarer, but it happens. I have had mainstream commercial DVDs freeze my machine so bad i couldn't even force quit. a complete freeze. Just pop it in as usual and then - uh oh! Hold the power button down till the screen goes blank. and like I said, sometimes working with images has caused the machine to lock up completely.

Anyway, I have one big piece of good solid advice. Buy Ted Landau's trouble-shooting manual for OSX. It has to be the one for your specific system. That would be Leopard or 10.5 (only the big number versions count.). He had one for Tiger, and I hope he has one for Leopard. They used to be called OSX Disaster Relief, but he changed as of my version to OSX Help Line. It may have a different title for your OSX.

This book is still the best investment I ever made after buying my computer (my first and only so far). It will save you sleep and add years to your life. Did you pay 300$ for Applecare? - you'll never have technical support on the phone again...

I recommend you don't leave it laying around waiting. Read it in your spare time, the way you would a Steven King novel. every horror a Mac user could face is detailed and explained in there, and Landau leads you safely out of the woods in every instance.

P.S. There are some basic housekeeping proceedures you might need to pay attention to.

• 
  Restart your computer regularly. when adding, deleting, or updating software, and even when making major changes in folder structure or moving, deleting, or renaming large numbers of files. a restart cures 90% of all probems. If you leave you're computer running without a restart, it starts to act wonky ( Last i read, Linux held the record for running something like 23 days without one.).
  [/li]
  
• 
  Chron jobs need to be run. Unix does this at set times by default, in the middle of the night. Either stay up all night working on your computer every so often (my solution :), or get one of the open source downloads from versiontracker or macupdate, like Onyx or Macjanitor.
  [/li]
  
• 
  Don't forget to run software update for OSX.
  [/li]
  
• 
  Also, use disk utility to run 'repair disk permissions'. These get out of wack.
  [/li]
  

The more and the longer you use you're computer, the more necessary these tasks become.

- Also visit some of the OSX troubleshooting sites like macintouch and macfixit.
- Sometimes it's taken me all night, but i've had really good results googling on terms specific to my problem. - and don't forget Apples own trouble-shooting forums! These actually have alot of great and in-depth advice and solutions.

[edited by: commanderW at 8:02 am (utc) on Jan. 8, 2009]

So, you advise I pull an all nighter once a week?

I have had my machine on for about two months now and it is acting kind of slow. It goes to sleep when I do, and wakes up when I do.

Should I reschedule cron jobs for like 6:30 am, when I am not here but when the machine is still awake?

So, you advise I pull an all nighter once a week?

There's a wide selection of little utilities that will run these CRON jobs for you, or reschedule them (just Google something like: mac os x cron jobs utility) or you can just go into the Terminal and run them yourself.

I've never noticed these CRON jobs speeding up my machine though. If your fast Mac is acting slow, my suggestions are: RAM, RAM, and RAM.

Recently my Mac was freezing up on me. Seemingly random stuff -- opening a directory window in the Finder, opening a simple text document, or a Photoshop file, saving a document, ftp'ing a file (in either direction).

Most often, the seemingly random stuff is bad RAM. In this case, it turned out to be a failing hard drive. Anything that involved reading from or writing to the disk froze it right up.

I'd run Apple's hardware test (check your system install disk), Disk Utility's Disk Repair (while booted from your install disk or a different drive), and Disk Warrior (while booted from the DW disk or a different drive).

If you have more than the minimum amount of RAM, you can try removing some of it to see if the problem remains. If the problem goes away, put it back in and take out different RAM. And so forth.

And you do have backups of everything important, right?

I think the problem is probably cat hair. I took it in for a look see two years ago, and that was the major problem. I noticed this afternoon that there was a bit of cat hair under the screen, and when I ran my hand along there I cleaned off a bunch of it. (There are two long hair cats here.) Anyway, it is running better now. The I mac air intake seems to be down there.

And even with all the cat hair, it is still miles better than the Vista machine.

Baruch,

Are you using an iMac? That would explain the intake being full of cat hair. We have more cats then normal people have ;) and this can cause overheating and other problems if you do not keep your intake screen clean.

I suggest once a week taking a dry cloth and running it along the bottom of the iMac to clean out dander and hair.

Also, get the free utility called iStat menus. This is an excellent way to monitor temperatures and fans in your Mac menu bar. It also monitors your cpu, ram, drives, network connection, bluetooth and more.