To repeat what I just said woth slightly different wording: Yes, my point was specifically referring to the difference between users who want the Titan X for supercomputing versus those who want it for gaming. You can have as many CUDA cards as you want but you face the same problem of limited PCIe bandwidth just like you do with gamers who want SLI. If your use case is CUDA and not gaming, then the usefulness of four Titans depends entirely on whether your algorithms are limited by memory, memory bandwidth, or computing power.