I booted up today into Ubuntu 6.06 and had this problem - its doubly odd because I have Ubuntu backed up onto an entirely separate partition, i.e. root and home are on a second backup drive, yet when I boot up into that drive the problem is still there!!!
It doesn’t happen in the Windows version.
Its something to do with transparency because if I move the window the squares stay stationary (on the platform that the model is standing on the effect happens at each of its faces dependent on what angle it is to the camera) - note the effect also affects the keys and buttons (you can see it on the word camera and above object mode).
Could my Radeon X800 card have gone funny? Any ideas?
Note problem was not there yesterday - 3D acceleration is unaffected and terminal output gives no errors.