Today I installed Ubuntu 13.04 on a Lenovo ThinkPad X220. It worked fine at first, but after the first round of updates and rebooting it GNOME Shell seems to have been broken. At first I was able to get into GNOME Shell but my wallpaper was gone. I restarted my computer again and this time I could not get into GNOME Shell at all, it just hangs at the login screen. I'm able to get into Unity and it too doesn't display my wallpaper, and sometimes a static image of the login screen will get "stuck" and become the wallpaper. I think my hard drive may be going bad and that may have something to do with it. The whole computer feels kinda sluggish and the hard drive is quite noisy.