I have exactly the same bug. It also happens with a Radeon HD 6850 with fglrx drivers installed.
"1) There are some weird graphical artifacts near the top of the screen that change as I type in my password."
This happens to me aswell. Afther this, lightdm restarts or crashes with a black screen.
It also appears to be completely random, happens about 1/3 of the time I start up the computer.
I have exactly the same bug. It also happens with a Radeon HD 6850 with fglrx drivers installed.
"1) There are some weird graphical artifacts near the top of the screen that change as I type in my password."
This happens to me aswell. Afther this, lightdm restarts or crashes with a black screen.
It also appears to be completely random, happens about 1/3 of the time I start up the computer.