Not really the same thing on the spec sheet even if the practical realities are somewhat closer- and I think the possible part we're discussing is more aimed at marketing bullet-points than any performance part missing from the inventory.
GTX 780 = 2304 shaders, 3GB GDDR5, 1:24 FP64
Titan = 2688 shaders, 6GB GDDR5, 1:3 FP64
Other possible combinations are therefore
2688 shader, 3GB GDDR5, 1:3 FP64 and 2688 shader, 6GB GDDR5, 1:24 FP64
You could also add 7Gb/sec effective memory if the GK 110's memory controller could be QA'ed for the speed. Running out of spec for OC'ed cards is generally a whole lot different from reference validation.
So buy the 6GB version. Just as you like 6GB isn't it conceivable that someone else would be happy to sacrifice 3GB to have 30-40% reduction in price?
Same argument. See above.
Titan : 2688 shaders....
K6000 : 2880 shaders. Titan is a salvage part...so you're lusting over a nerfed part already
Tell that to Jen Hsun and Rory, and provide an alternative income stream for them to recoup their loss of ROI.
It's a nice idea...but basically an idealized scenario totally divorced from reality.
HD 7870XT (Tahiti LE) 75% enabled die (shaders). Introduced 5 months after the fully enabled part.
GTX 660Ti (GK104-300) 88% enabled die (shaders). Introduced 5 months after the fully enabled part.
HD 6930 (Cayman CE) 83% enabled die (shaders). Introduced 12 months after the fully enabled part.
GTX 560Ti 448SP (GF110-270) 88% enabled die (shaders). Introduced 13 months after the fully enabled part.
HD 5830 (Cypress LE) 70% enabled die (shaders). Introduced 5 months after the fully enabled part