i posted this in the apple support discussion site as well. hoping to get some wisdom from macrumors! hi. i've got a 1st gen Core Duo 1.83gHz macbook that has developed a concerning problem: it randomly goes to sleep. no, not random shutdown, it randomly goes to sleep. the sleep light is blinking and when i touch the trackpad, it'll wake back up. sometimes it'll do this multiple times in a row, and i can barely get back in to shut it down. this is happening with normal web surfing, nothing processor intensive. it doesn't seem to happen when the macbook is "cool", as in the first hour of use or so. but only after a few hours of use. some of the things i've tried: 1) resetting SMU 2) resetting PRAM 3) repairing disk permissions (using Onyx) 4) removing the battery and going off wall power 5) creating another user and logging into the new user in all cases, the random sleep continues. i'm afraid this may be the beginning symptoms of the dreaded Random Shutdown Syndrome (failing motherboard/heatsink) that has plagued 1st gen macbook. unfortunately, i was stupid and didn't purchase applecare and now my macbook is past it's 1 year coverage, so taking it into Apple will cost me out of pocket. one thing i haven't tried is a complete disk wipe and reinstall. anyone have any more suggestions before i bite the bullet and bring my macbook into Apple? could this possibly be faulty RAM (i have kingston after-market RAM 1gb). thanks in advance.