I have a Gateway 600ygr and just recently it would intermittently not boot. It wouldn't even get to POST. Initially, I thought it was the bios until the last time it did boot I went into the bios made some minor changes and saved it. This to me was like flashing the bios which should have corrected any corruption within it. Unfortunately, it didn't work.
Could the bios chip itself be bad and causing these symptoms? If not, could it be something with the power supply? I'm leaning towards the later because I have two Toshiba Armada M300's that are doing the same thing. They died about 6 months prior and within a month of each other. We do get frequent power outages where the power goes out for just a few seconds and none of the laptops were surge protected. I'm just not sure what part of the laptop would be affected by this. They don't seem to work with battery power either.