Hi, I don't understand your problem : You say no texture applied, but your material shows a texture. Please be more precise.
French Blender user - CPU : intel Quad QX9650 at 3GHz - 8GB of RAM - Windows 7 Pro 64 bits. Display GPU : GeForce GTX 480 (2 Samsung 2443BW-1920x1600 monitors). External GPUs : two EVGA GTX 580 3GB in a Cubix GPU-Xpander Pro 2. NVidia Driver : 368.22.
@roubal... he means object 1 has no image, object 2 has images as per attachment, object 3 has images as per attachment.
@ larmannjan... I notice that for Objects 2 & 3, roughness input is set to image, but there is no map listed in the text field. If you do not actually have a roughness map set input type to none. If you have a roughness map either it is not selected or not actually available in blender. Hope that helps.
For my own, I noticed that disabled texture slots in a material returned an error message.
French Blender user - CPU : intel Quad QX9650 at 3GHz - 8GB of RAM - Windows 7 Pro 64 bits. Display GPU : GeForce GTX 480 (2 Samsung 2443BW-1920x1600 monitors). External GPUs : two EVGA GTX 580 3GB in a Cubix GPU-Xpander Pro 2. NVidia Driver : 368.22.