G4 crashes after several minutes

ok i am trying to rely a problem from my son who is deployed and can not access the net for help (he is currently using someone else's pc to contact me), he is using an old g4 1.25 with 2 sticks of 526 memory recently it crashed on him after several minutes, i know that there is additional info such as which os he is running and whatever info i will get from him but for now here is the error message that shows up on his screen any help will be greatly appreciated

the computer started to freeze up after about ten minutes of use. After restarting the computer several times and this happening to it, an error screen popped up. My desktop was intact except for the error coding which was in what appeared like a DOS format. Here is what was on the screen :
System failure: CPU=0, code = 00000001 (corrupt stack)
Latest crash info for CPU0
Pc=0x000AC0D8; MSR=0x00001030; DAR=0x00013CBF; DSISR=0x00005F81; LR=0x00003820; RI=0xFFFCEAE7; XCP=0x00000098(system failure)

Backtrace terminated- unaligned frame address: 0xFFFCEAE7

Proceeding back via exception chain: exception state (sv=0x020449C80)
PC=0x076E4298; MSR=0x02083000; DAR=0x0000BCBF; DSISR=0x00005F81; LR=0x000029AC; RI=0xFFFCEBC7; XCP=0x0000001C (0x700_program)

Backtrace terminated unaligned frame address: 0xFFFCEBC7

EXCEPTION STATE (sv=0x3B623780)
PC=0x000AF53C; MSR=0x00009000; DAR=0x216BF040; DSISR=0x40000000; LR=0x000340A8; RI=0x1768BE30; XCP=0x00000024 (0x900-decremeter)

Backtrace: 0x00034050 0x000A9714

Exception state: (sv=0x00B48280)
PC=0x00000000; MSR=0x0000D030; DAR=0x00000000; DSISR=0x00000000; LR=0x00000000; RI=0x00000000; XCP=0x00000000 (unknown)

Kernal version:
Darwin kernel version8.11.0: wed oct 10 18:26:0017~7/Release_PPC memory access exception (1.0.0) ehternet MAC address: 00:00:00:00:00
ip address: 0.0.0.0
waiting for remote debugger

To get the ball rolling. Has the system been changed in any way, before crashes started to appear? Something new memory or new applications?

That looks pretty nasty. If he can't even use OS X at all, I'd reset the PMU and NVRAM. If this doesn't work... post again.

http://docs.info.apple.com/article.html?artnum=14449

Go there and find his model of PowerBook in the list, and carry out the instructions for resetting the PMU for that model. Note that his clock will have to be set again after this.

first new memory has been installed, just after the hollidays he swapped out 1 stick of 256 for 1 stick of 512, everything was fine he was running with 867 of ram, then most recently he replaced the other stick of 256 with another 512, both memory sticks were purchased from crucical but at seperate times, i will tell him to put the original memory back in to see what effect it has, and i will look at the link that was posted to reset, what does PMU and NVRAM stand for thanks for the help

one question about resetting the power unit it says Warning: Resetting the Power Manager on any PowerBook or iBook will permanently remove a RAM disk, if present, and all of its contents. is this the same as formatting a harddrive

mrelmo said:

one question about resetting the power unit it says Warning: Resetting the Power Manager on any PowerBook or iBook will permanently remove a RAM disk, if present, and all of its contents. is this the same as formatting a harddrive

Click to expand...

No. I've done this to my machine before. The most you have to worry about is losing the date/time and possibly a few customized login settings.

thanks that will be tried after the original ram is put back in