I have a Macbook Core Duo (specs, with memory upgraded to 2GB crucial and the Hard Drive upgraded to 160GB Fujitsu, both by previous owner), and recently it has been getting Kernel Panics on a regular basis. I bought it used off of Craigslist about to years ago and it has always been a little iffy, but this is the first time I've encountered Kernel Panics. I recently upgraded from Leopard to Snow Leopard 10.6.7. I've been getting Kernel Panics after having it turned on for about 15 minutes. It has occurred while using iTunes, the Java game Spiral Knights, and while using memtest. I have tried resetting the PRAM, and repairing the disk and disk permissions. I would like to do a Hardware Test, but the boot disk that came with the computer is scratched to hell. I upgraded to Snow Leopard using an external Hard Drive as the boot disk, but I can't find a way to use that drive to do the hardware test. Since I haven't been able to run that test, I tried mem test/remember to see if the memory is ok. If I choose to test 1 GB it runs fine and gives a positive response, but if I choose all it gets a Kernel Panic about halfway through. I tried booting to safe mode to do the mem test, but it got a Kernel Panic there too. Is there anything else that I can do to find the source of these crashes?