12.04 upgrade won't let me boot in

[Guest]

Hi, I, just upgraded to 12.04 enter my username and password and the screen goes black. Nothing happens.
It's a AMD 550 BE with 8 Gig ram with a 4870 video card. This is my work computer and I'm a bit cross. Help please.
Steve

[doctordruidphd]

Sounds like there may be a video issue.
You can try disabling compositing, and see if that lets you boot to your desktop (effects won't work).

You will need to edit your ~/.kde/share/config/kwinrc file. Look for the [Compositing] section, find the line that says Enabled=true and change it to Enabled=false
Save the edited file, then try restarting.

[Guest]

Thank you. I actually got in. On the log in screen there are 4 options which I've not come across before. I eventually tried KDE workspace and it let me in. This is odd, I had tried to login from the terminal and updated etc but I'll set it up for an auto login from now on.
Steve.