Computer demands hard Restart - applies to all 3 Macs at work

Question

To preface my question: I work for a publishing company as a graphic designer. Our department has 3 Power PC G5s w/ dual 2 GHz processors, 3.5 GB DDR SDRAM running OS X version 10.4.11. Main applications used are QuarkXPress 6.5, Photoshop CS, Ilustrator CS, Acrobat 6.01, Office 11.3.8.
These computers had been used daily for the past 3 years without a single kernel panic (each running varied versions of Panther with 2 GB of memory). Problems started when all computers were upgraded to Tiger 10.4.11 and 1.5 GB of extra memory was added. Each of the computers now kernel panics at least once every 2 days. Our IT support staff switched out the new RAM and the problem persists.
Does anyone know or suspect what could be causing this problem and the best way to solve it?
Just a note: We are all upgrading to Leopard in the next week or so. Also upgrading to CS3 creative suite. Will upgrade possibly solve this problem?
Thanks!

Answer 1

There's a panic log that's usually saved when it panics. It can be kind of tricky to read them, but sometimes they're helpful in figuring out what caused a panic. You can find it by opening the Console application from your Utilities folder, and navigating to the file called "panic.log" in /Library/Logs.
What you're looking for is anything in the backtrace section. What you're looking for is the cause of the panic in the line line where it tells which CPU panicked. It'll say "panic", then have some text describing the panic. Best is if it says something like "uncorrectable machine check," since that's pretty descriptive of a hardware error.
Second best would be some other message, but a clear set of kernel extensions in the backtrace section:
Kernel loadable modules in backtrace (with dependencies):
com.apple.iokit.AppleAirPort2(401.2)@0x22400000
dependency: com.apple.iokit.IONetworkingFamily(1.5.0)@0x21592000
dependency: com.apple.iokit.IOPCIFamily(1.6)@0x1d82e000
In this case, if you saw "uncorrectable machine check" and then those kernel extensions in the backtrace, you know you most likely have a hardware problem with your AirPort card. What you're looking for is either a pattern or no patter.
If al three Macs have very similar, or the same, panics, look into what was changed most recently on all three. Since you did an upgrade, maybe some driver or kernel extension needs to be updated. If the panics are all different, and don't have a discernible pattern, that might be bad RAM.
If nothing jumps out at you, post one or two panics here.
I'd still be somewhat suspicious of the RAM installation. My feeling, not based on scientific testing mind you, is that the RAM in the G5s is pretty temperamental. We seemed to get a lot of bad modules, or installing more RAM in them seemed to cause problems with the old RAM more often than with the G4s before them or the Intels after.
charlie