Quick one tonight - I’m currently attempting to breathe some new life in to an old laptop (a Sony Vaio purchased to kick off my University days in Summer 2002). As you’d expect, my first decision was to switch to Ubuntu rather than chug along with Windows XP, so I ran the latest official CD image. When the X Server (Graphical Interface) loaded up, the top half of my screen was fine and displayed as normal, however the bottom half was a hazy mash of lines and squiggles (official technical term there).

Having restarted the machine several times, disconnected USB devices and so on as per the usual suspects, the problem persisted. A random decision to choose “Log Out” instead of “Shut Down” led me to a login screen on the Live CD, which auto-logs in to the default ubuntu user again after 10 seconds. This time when it logged in, the screen displayed correctly.

No idea what caused all this, but in case you’re hitting the same wall I thought I’d put what worked for me online so you have something to try.