I've just completed a fresh first install of Ubuntu 64-bit 12.10 and very regularly the on-screen text is distorted.
How could I fix this?
Issues with the pre-installed drivers are rather common in Ubuntu 12.10.
I haven't tested them myself (because I don't have an nVidia card), but the drivers from X Updates seem to solve those issues for a lot of people.
You can install the drivers by executing the following commands from a terminal: