Alright, first thing's first: This belongs in Technical Difficulties. Either a moderator can move it to that section of the forum or you could do it yourself via the Edit button above your post.

Ok then, down to business. It would help if you could give a little info, because at the moment we know very little about what's going on at all. You should read and follow this post before continuing, because it's very likely that one of these things are related to your issue.

If that doesn't help, come back here and post the following: (No, you don't need to use a fancy list.)

• What is your operating system? (AKA OS. This could be Windows XP, Windows 8, Mac OSX, Debian Linux, etc.)
  • If you have a Linux OS, do you know what desktop you are using? I.e. Gnome, KDE, or Xfce?
• Do you have some graphics manager or control center which could control the way 3D games work?
• Do you use the browser launcher, a desktop shortcut, Steam, or another game launcher to start Spiral Knights?
• Have you tried going into fullscreen while having the graphics quality set to low?
• Could you post your projectx.log file's contents? It can be found in the root directory of the Spiral Knights. (I can't be more specific until I know your OS, because this varies per OS.)

Good luck!