Specs: 12" Powerbook (last version of the PPC series) Ram: 1.25 gigs HD: 80 (5400 rpm) Processor: 1.5 ghz OSX: Tiger 10.4.10 or later. Problem: Powerbook turns itself off after less than one minute of being active. Then after shutting itself off, it attempts to turn on moments later (Apple "On" horns are heard) but never succeeds (back to black screen). It continues to do this until I take out the battery (in fear of laptop doing more bad than good by restarting itself). Personal Diagnosis: Hard-drive failure. (one click of the HARD-DRIVE is heard before turning itself off - cycling of the HD stops) Possible Diagnosis: Logic Board failure (which was just replaced 4 months prior to this) Notes: Happens with and without power adapter plugged-in. I have attempted resetting the PRAM No I don't have AppleCare on this anymore. Any help? Should I send it in?