The NVIDIA GeForce GTX Titan has nothing against NVIDIA's latest creation. Meet the GeForce GTX Titan Z. This is the mother of all video cards right now.
The GeForce GTX Titan Z has two, count them, two Kepler GPUs on board and 12GB of memory. It's built for the next generation of gaming meaning 5K resolution. Of course, this power doesn't come cheap as you'll need to spend about $3000 to get this in your gaming rig.
It sounds like overkill, but hey why not. If you got the money, then go ahead and pick this one up to really turn your PC into a powerhouse.