I've recently had trouble with my old G5 (fans running flat out while the system locks up),
I came home to find this

I took the photo before Christmas I think, and have just found it. Anyway here it is.

You know, that is rather cool.

Switch it off, let it cool down and check the vents and fans and the air flow path through the system.

On an iMac G5 there is a vent behind the stand which isn’t visible unless you know that it’s there. This can get clogged with muck and bullets. My G5 iMac started playing up - I checked the vents underneath, which were clear. I found the back vent by accident. I unclogged that and it started working normally again.

Try booting into the Hardware Tests to check the components for problems, in particular the logic board and RAM.
You'll find Hardware Tests for your particular Mac on your original System Install DVD - boot while holding the "D" key.
Run the "Extended Tests" and report back any errors discovered.

That bottom part, is it a piece of software you had running at the time?
I'm just having trouble comprehending this is for real, that's all - it's not 'shopped is it?
What is the "myology" text at the bottom?
Sorry, I'm just naturally suspicious!!

Ha, I ran the Hardware test and got this result



Rebooted and half an hour later the same thing happened.
Here is the system info & a crash log.

System Configuration
Model: PowerMac11,2, BootROM 5.2.7f1, 2 processors, PowerPC G5 (1.1), 2.3 GHz, 2.5 GB
Graphics: kHW_NVidiaGeForce6600Item, GeForce 6600, spdisplays_pcie_device, 256 MB
Memory Module: DIMM0/J6700, 1 GB, DDR2 SDRAM, PC2-4200U-444
Memory Module: DIMM1/J6800, 1 GB, DDR2 SDRAM, PC2-4200U-444
Memory Module: DIMM2/J6900, 256 MB, DDR2 SDRAM, PC2-4200U-444
Memory Module: DIMM3/J7000, 256 MB, DDR2 SDRAM, PC2-4200U-444
PCI Card: GeForce 6600, display, SLOT-1
PCI Card: Apple 5714, network, GIGE
PCI Card: Apple 5714, network, GIGE
PCI Card: pci1095,3132, sppci_othermassstorage, SLOT-2
Serial ATA Device: Hitachi HDT721010SLA360, 931.51 GB
Parallel ATA Device: PIONEER DVD-RW DVR-110D
USB Device: Hub in Apple Extended USB Keyboard, (null) mA
USB Device: Apple Optical USB Mouse, (null) mA
USB Device: Apple Extended USB Keyboard, (null) mA
FireWire Device: unknown_device, unknown_value, unknown_speed

Problem Details
Interval Since Last Panic Report: 0 sec
Panics Since Last Report: 1
Anonymous UUID: 8E5DEE53-17A0-4BC5-9533-7A8740E57736

Sat Nov 27 15:52:51 2010
panic(cpu 0 caller 0x000AD128): simple lock (0x03B3843C) deadlock detection, pc=0x00030AC8

Latest stack backtrace for cpu 0:
Backtrace:
0x0009CC88 0x0009D63C 0x00029DA0 0x000AD128 0x00030AC8 0x000AC898 0x000251A0 0x000B45CC
0x2E3BDF3D
kmod scan stopped due to missing kmod page: 00000000
Proceeding back via exception chain:
Exception state (sv=0x6629c500)
PC=0x928ED1D8; MSR=0x0000D030; DAR=0xE0035000; DSISR=0x42000000; LR=0x928F4100; R1=0xBFFFFA50; XCP=0x00000030 (0xC00 - System call)

BSD process name corresponding to current thread: Unknown

Mac OS version:
9L31a

Kernel version:
Darwin Kernel Version 9.8.0: Wed Jul 15 16:57:01 PDT 2009; root:xnu-1228.15.4~1/RELEASE_PPC

System uptime in nanoseconds: 10409497843061
unloaded kexts:
(none)
loaded kexts:
at.obdev.KUC 1.2.63
com.Logitech.Control Center.HID Driver 2.7.0
com.SiliconImage.driver.Si3132 1.1.9
com.apple.filesystems.autofs 2.0.2 - last loaded 942032096
com.apple.driver.AppleTopazAudio 2.5.8f1
com.apple.driver.AppleOnyxAudio 2.5.8f1
com.apple.GeForcePPC 5.4.8
com.apple.nvidia.nv40halppc 5.4.8
com.apple.driver.AudioIPCDriver 1.0.6
com.apple.driver.PowerMac11_2_ThermalProfile 3.4.0d0
com.apple.driver.AppleTexasAudio 2.5.8f1
com.apple.driver.AppleHWSensor 1.9d0
com.apple.driver.AppleTexas2Audio 2.5.8f1
com.apple.driver.AppleSCCSerial 1.3.2
com.apple.driver.IOI2CMaxim1631 1.9d0
com.apple.driver.AppleDACAAudio 2.5.8f1
com.apple.driver.IOI2CSMUSat 1.9d0
com.apple.driver.IOI2CLM7x 1.9d0
com.apple.iokit.IOFireWireIP 1.7.7
com.apple.driver.AppleK2Driver 1.7.2f1
com.apple.driver.IOI2CMaxim6690 1.9d0
com.apple.driver.AppleSMUMonitor 1.9d0
com.apple.driver.AppleI2S 1.0.1f1
com.apple.driver.IOI2CPulsar 1.5.2d0
com.apple.driver.IOI2CControllerSMU 1.1.1d2
com.apple.driver.AppleFileSystemDriver 1.1.0
com.apple.driver.AppleUSBHIDMouse 1.2.4b3
com.apple.driver.AppleUSBMergeNub 3.5.2
com.apple.driver.PioneerSuperDrive 2.0.9
com.apple.iokit.SCSITaskUserClient 2.1.1
com.apple.driver.XsanFilter 2.7.91
com.apple.iokit.IOATABlockStorage 2.0.6
com.apple.driver.AppleUSBHub 3.4.9
com.apple.iokit.IOATAPIProtocolTransport 1.5.3
com.apple.iokit.IOUSBUserClient 3.5.2
com.apple.driver.AppleK2SATA 1.0.4f2
com.apple.driver.AppleGPIO 1.3.0d0
com.apple.driver.MacIOGPIO 1.3.0d0
com.apple.iokit.AppleBCM5701Ethernet 2.2.3b1
com.apple.driver.AppleMPIC 1.5.3
com.apple.driver.AppleI2C 4.0.0d2
com.apple.driver.IOI2CControllerPPC 1.1.1d2
com.apple.driver.AppleFWOHCI 3.9.7
com.apple.driver.AppleKauaiATA 1.2.1f4
com.apple.driver.AppleK2SATARoot 1.0.5b1
com.apple.driver.AppleUSBEHCI 3.4.6
com.apple.driver.AppleUSBOHCI 3.4.6
com.apple.driver.AppleK2 1.7.2f1
com.apple.driver.AppleSMU 1.2.1d1
com.apple.driver.AppleMacRiscPCI 3.4.0
com.apple.driver.AppleCore99NVRAM 1.1.1
com.apple.driver.AppleFlashNVRAM 1.0.5
com.apple.security.seatbelt 107.12
com.apple.nke.applicationfirewall 1.8.77
com.apple.security.TMSafetyNet 3
com.apple.BootCache 30.4
com.apple.driver.DiskImages 199
com.apple.driver.AppleMacRISC4PE 2.0.4d9
com.apple.driver.AppleOnboardAudio 2.5.8f1
com.apple.driver.AppleDBDMAAudio 2.5.8f1
com.apple.NVDAResmanPPC 5.4.8
com.apple.iokit.IONDRVSupport 1.7.3
com.apple.iokit.IOGraphicsFamily 1.7.3
com.apple.iokit.IOSerialFamily 9.4
com.apple.driver.AudioI2SControl 2.5.8f1
com.apple.driver.Apple02Audio 2.5.8f1
com.apple.driver.Apple02DBDMAAudio 2.5.8f1
com.apple.iokit.IOAudioFamily 1.6.9fc5
com.apple.kext.OSvKernDSPLib 1.1
com.apple.driver.PowerMac11_2_PlatformPlugin 3.4.0d0
com.apple.driver.SMU_Neo2_Plat`

Should I be saving for a Mac Pro now?

Is that OS 8 or 9?

Mark

This bit could possibly be the offending bit...

Not sure exactly what it is, but I suspect it could be a kernel panic - though normally when that happens you get the message in four languages saying that you need to restart - I've never seen anything like you posted above.

My next course of action would be to remove anything that you've added to the G5 since you bought it - i.e. anything non-Apple, including extra RAM, PCI cards, etc. Once you've done that, check for the same error - if it goes away, then it's probably one of these additional items you've added, either software (check for latest drivers for each device) or possibly hardware (replace this component). What upgrades, if any, have you done to the G5 since purchasing it?

If the problem still persists, consider doing an "Archive & Install" of OS X 10.5 - it's one of the options when you re-install the system - just select "Archive & Install" and tick the "Preserve users and network settings" checkbox. This will give you a brand new system, but retain your home folders and network settings. Remember to check Software Update for any patches issued since 10.5.8 was released too.

DOH! slaps forehead.

In the past I have installed OS X on a new hard drive and removed the new RAM I bought. The trouble still occurred. But for some reason I haven't tried removing the eSATA card and trying it. I'll give it a go and report back.
Thanks again.

Wow

That's one hard panic.

Personally, and having searched for a few things, my money's on a bad 3rd party kernel extension that was installed during a legit installation. You see it all the time with *nix systems where some lazy developer has bypassed the OS instead of doing it properly.

However, not being a Mac man I can't help too much. Personally, however, I'd start by looking at drivers - they're usually the worst.