This is a reminder that Microsoft's new version of Windows, "Vista" has serious issues with OpenGL-based software and should be avoided for the time being. 
Only in the last few weeks have all of the major graphics card companies finally begun to release Vista drivers with true OpenGL support.  Thus, please allow a few months for the bugs to shake out before expecting PyMOL (and other OpenGL-depedent programs) to run well on Vista.
If you buy a new Windows PC or laptop soon, be sure to check what operating system comes installed -- you may need to specifically ask for Windows XP.
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