The number of CPU cores required for VR can vary depending on the specific VR system and software being used, as well as the complexity of the VR application or game. However, most modern VR systems and applications require a minimum of at least a quad-core CPU, which means a processor with four physical cores.
It is recommended to have a CPU with higher clock speeds and more cores if you want a smoother VR experience, especially when running demanding VR applications or games. Therefore, a six-core or eight-core CPU with high clock speeds would be ideal for VR.