Apps keep quitting on my PowerBook G3

[PowerBook User]

I keep having applications on my laptop quit unexpectedly. The worst programs are Firefox and Netscape, but I've also had iTunes quit and Finder restart unexpectedly. I found this in the Finder crash log:
"Exception: EXC_BAD_ACCESS (0x0001)
Codes: KERN_PROTECTION_FAILURE (0x0002) at 0x00000128"
and this in iTunes:
Exception: EXC_BAD_ACCESS (0x0001)
Codes: KERN_INVALID_ADDRESS (0x0001) at 0x80690010"
This happens quite often. Sometimes my hard drive also spins alot, even when I'm not using it. I've tried DiskWarrior, Disk Utility, and repairing permissions. I also thought it could be a RAM problem, so I replaced all the RAM in my computer with brand new sticks, but I still have the problem. I have a PowerBook G3 Pismo 500 MHz, 512 MB RAM, 40 GB hard drive, and Mac OS X 10.3.9. I'm thinking the hard drive could be going bad, but don't want to buy a new one if it won't help. Thanks in advance for your help!

 

[mad jew]

Have you run the Apple Hardware Test? It's not perfect, but it may show us something.

 

[theISHkid]

Where and what is the Apple Hardware Test?

 

[mad jew]

Well, if you have the original discs for this machine, the Apple Hardware Test should be installed on one of them. Boot from this disc and run the tests to see if it picks anything up.

 

[PowerBook User]

Have you run the Apple Hardware Test? It's not perfect, but it may show us something.

I don't think I tried that. I'll see if I can find the discs in the next few days. Thanks!

 

[mad jew]

Okay mate, tell us how it goes.