GDDR5 - RMBS solution too far ahead of the curve?

As reported in EE Times Asia the GDDR5 graphics controllers major players (AMD, Nvidia and Intel) are leaving Rambus's solution out of their equation:

(Joe) Macri, (senior director of circuit engineering for AMD's graphics group) said advanced signaling technologies from Rambus will not be competitive, in part because they use a differential (two-wire) approach rather than the single-wire technique in GDDR5. The extra wire typically requires more pins and power. "We don't think a differential solution make sense until you get to speeds of 8- to10Gbit/s," he said.

Michael Ching, director of product marketing at Rambus believes that in the end, Rambus is the solution and the end is as early as 5-6GHz, maybe even 4 GHz:

"That's pretty much the end of the line for the single-ended approach," Ching said, adding that the Rambus XDR approach can consume less power than single-ended techniques. "Our analysis shows differential technology results in lower power even at 4 GHz or so, and the difference between the two grows as you go faster," he said.

And good news for Rambus is coming:

Within weeks, Rambus will disclose its XDR-2 technology, which will start at 8 GHz and has been demonstrated at 16 GHz, Ching said.

. . . XDR can be found as a graphics link in a Toshiba notebook. Toshiba is also using XDR in an HDTV chipset.