Heya guys. I recently acquired an old Tibook M8407 model. When I turn it on it runs fine for sometimes about a minute (sometimes less) before it just turns itself off! After it turns itself off I'll hit the power button and it emits a high pitch squeal from the machine whilst holding the button. If I then remove the battery from the Machine depending on how long I leave the battery out and put it back in, it will then power up for a short amount of time. Sometimes I can get it to the desktop and open System Profiler for example, other times it gets as far as the Apple grey screen. I've ordered a power adaptor as I didn't get one with the machine but as far as the battery indicator goes, it's on 96% and all four green lights are on the battery indicator on the base. Has anyone heard of any problems like this before? I believe it's running a 500mhz processor and has 512mb of Ram. Thanks in advance!