Comment 6 for bug 1004197

I think you are wrong about login. Try to use some full screen program, for example midnight commander. When you type `mc' in the black screen, you will see a part from the bottom-right corner of the well-known blue mc panel in the top-left corner of the window. I think that means the whole login process (rsa key authentication, pam things, bash starting etc.) runs as normal, just the screen position is bad.

When you use password authentication you can log in 'blindly'. Of course you are not able to see the prompts, because they are not in bottom-right corner.