⟐ Answer edited October 25, 2013 at 13:58 MST

Deeper explanation…

Set the computer on a table, turn it on, and it works perfectly. However, if you pick it up off the table and slightly twist the base, the screen goes dark and a few other things happen (explained in a moment). It’s a specific twisting action; with the computer open, the hard drive is under the right palm rest and the PCMCIA cage is under the left palm rest. If you apply pressure on top of the right palm rest and below the left palm rest, the base will slightly twist so that the right side (the hard drive side) is lower. In that position the screen goes black (as if the video cable were unplugged) and the hard drive stops accessing; the computer is effectively “crashed” at this point. It doesn’t respond to a network ping or anything. Twist it back so that the left side (the PCMCIA side) is lower and the screen and hard drive both “wake up” and things continue like nothing ever happened. As long as the computer is kept flat/level/twist-free, it will work perfectly.

Once in awhile, like when I’m experimenting by twisting it multiple times, the screen will get some odd artifacts on it. Even more rarely, the computer will actually crash (complete lack of all activity).

In testing…

• Definitely not software-related as I’ve clean-installed the OS, so nothing bad is there.
• Disconnecting the on-board video cable and driving only an external screen does not solve the problem.
• Removing the keyboard and track pad assemblies does not solve the problem.
• Unplugging, cleaning, and reseating every internal cable/harness/etc does not solve the problem.
• Removing the battery and running only on AC power does not solve the problem.
• I was thinking perhaps there was a short happening below the ATA bus (not SATA) at the lower enclosure, so I insulated it with a bit of electrical tape. No help there.

Clearly there’s some kind of intermittent contact issue happening. Twisting in one direction disconnects “something” and twisting in the other reconnects it. I just have no idea where I might look to find where that “something” might be. Ideas?

⟐ Commented June 08, 2020 at 10:51 MST