I had an "OpenGL Error" some years ago. And sometimes got it nowadays. However this isn't caused by any normal causes, it was because of computer overheating. So I did clean up my computer's inside with vacuum and the error was solved. Too much dust causes overheating, and this caused me OpenGL errors. I did so much digging, but couldn't get rid of it until I sucked the error into my vacuum cleaner. You should do clean it quite often anyway.
1. update to 2.60b, both updates are in our download section 2. update your video card drivers... see faq under OpenGL error, or the link under our faq link in the nav menu on top left of page, or the OpenGL sticky in the help section of our forums, as well as every propper reply in this thread