Sick Windtunnel G4 - Freezes and Panics

Have you blown the dust out layely?

Does it do better if allowed to cool?

One way to test is to Safe Boot from the HD, (holding Shift key down at bootup), run Disk Utility in Applications>Utilities, then highlight your drive, click on Repair Permissions, Test for problem in Safe Mode...

PS. Safe boot may stay on the gray radian for a long time, let it go, it's trying to repair the Hard Drive

Reboot, test again.

If it only does it in Regular Boot, then it could be some hardware problem like Video card, (Quartz is turned off in Safe Mode), or Airport, or 3rd party add-on, Check System Preferences>Accounts>Login Items window to see if it or something relevant is listed.

Check the System Preferences>Other Row, for 3rd party Pref Panes.

Also look in these if they exist, some are invisible...

/private/var/run/StartupItems

/Library/StartupItems

/System/Library/StartupItems

/System/Library/LaunchDaemons

/Library/LaunchDaemons

Do you have the AHT disc?

If not, download and burn AHT v1.2.6 to CD and test your machine:

http://www.info.apple.com/support/aht.html

Test memory with Rember or Memtest X.

No PCI cards or such installed, right?

If so, remove for troubleshooting purposes.

Have a second hard drive or spare volume? Clean install OS X and see how it runs.

KPs and freezes aren't always hardware.....

Doesn't sound prommising, but anything from a failed hard drive to a failed CPU could be the issue.

Will the machine start up in Open Firmware? If it will, you can check the status of some of your hardware.

Please read, learn and apply the following:

http://osxbook.com/book/bonus/ancient/whatismacosx/arch_boot.html

Of particular interest are in examples 2 and 3 for checking the RAM report and the CPU report.

I was able to reinstall the OS

Good. Progress is good...

Since it's booting, Open Firmware boot is likely unnecessary (for now).

Check the System Profiler/Hardware for proper reports of memory and CPU.

Check the Diagnostics report.

Open Console and look for logs relating to failed processes after sleep wake event.

Pull all but the current boot drive. Lets limit possible suspects.

Pull all PCI cards (if any).

Since it's running, download Memtest X or Rember and test your RAM.

Testing all RAM in Single User mode (use Memtest) is best.

I'd test regardless of the system report.

If the RAM test is clean, then we have eliminated another big possibility.

Would a replacement 1/2 AA help?

I always replace batteries in stubborn machines.

Help, or not, it removes doubt.

Did you pull out all the extra drives?

Reseat the RAM?

I'd consider replacing the Thermal Paste between the CPUs & Heatsink, it could have lost it's properties.

jmac can recommend the best one & way to do it.

Does it take a bit longer to panic if it's cooled?

Look for a dark spot on or around the CPU chip on one or the other of the processors.

While you are there, r&r the thermal compound.

9AE7FE0E-0CF2-4A7C-8003-489B282582BC.html

Heck, pull and reseat the processor card.

Use Arctic Cooling MX-2, 3, or 4, whichever is easy to find (likely 4).

Excellent, safe, long lasting, best cooling.