I have probably similar problém like Jay-S. Vegas Pro 20. Some Window goes black during editing and rendering. For more demanding projects, the program is slowed down and cuts quickly. I tried re-installing Vegas many times, turning off gpu acceleration, installing the vegas driver, uninstalling other drivers. Win 10, NVIDIA Quadro K5200, CPU 2,6G, 32GB DDR3. Please help me. Thanks very much!