This is usually because of using an unsupported graphics chip set or out of date drivers.
What is the OS you are running Creo on, what is the graphics chip set? Are there other users you know with the same hardware who don't have the problem?
Most of the time it is from Intel Integrated graphics or a Radeon card.
You can shut off the graphics acceleration by adding "graphics win32_gdi" to the config.pro file and restarting Creo.
If that solves the problem, then look at changing the graphics card or trying different drivers. Sometimes the latest drivers or drivers supplied by the computer maker are not the best ones to use with Creo; there are too many combinations to make a comprehensive list, but most people with this problem find a working driver without too much difficulty.
