I just experienced a very strange and puzzling problem on my machine that I can't seem to get sorted out.

I was running Windows on a second partition, and everything was working great. I then went to restart into Linux, and noticed that X wouldn't start. Everything was displayed in super-low resolution, so I tried reinstalling my NVIDIA driver. I started seeing all of these I/O error problems, so I figured that my SSD was bad.

After a bit more playing around, I ran fsck on the drive when mounted from a startup disk as well as badsectors and everything looked great. The SMART drive tests all passed and again, everything was looking good, so I rebooted again and still, no joy. I started then getting some weird USB errors, so I followed someone's advice and unplugged my computer's power supply, then started back up again and my graphics looked a lot better in the BIOS and in the boot logo, but X still wouldn't start.

I then found out that my main boot drive was being mounted read-only for some reason.

What's going wrong? I've done some pretty extensive tests on the SSD from a startup disk such as writing massive files, reading big files, running filesystem checks on the entire disk, and everything is looking great, until I try to boot. Whenever I try installing the drivers with apt-get, I get a ton of ata error messages looking like this:

How can I diagnose what's going wrong and fix it so I can get back to work?