After loading a texture the data is uploaded to the GPU asynchronously. The Resources.UnloadAsset call will delete the Texture2D object but the actual texture data is kept around until the async texture upload completes. In this specific case the memory increases to an amount larger than the available memory which results in a crash. Setting the virtual memory page file in your OS larger will prevent the crash. Unfortunately we cannot handle the out of memory better at the moment. The texture operations will need to be spread over multiple frames to keep the memory usage lower. We will update the documentation to specify more clearly that the memory allocated for certain resources can be kept around longer if it is referenced by the render thread (which is the case for uploading resources).