1. PCI-E 16x/8x/4x/2x slots are sufficient to run OctaneRender®, while PCI-E 1x slots are not, as it slows down data transfer too much.
  2. You can share PCI-E bandwidth by mixing 16x and 8x slots.
  3. It is best to use two or more video cards of the same speed and VRAM configuration when using them with OctaneRender®.