EE Times writes NVIDIA chief scientist William Dally said that he believes low-cost organic substrates paired with new I/O techniques represent the best path to 3D chip stacks. The graphics firm may experiment with such techniques as early as next year in preparation for Volta, a 2015 GPU with stacked DRAM.
Chip stacking is increasingly seen as an alternative to moving to the next semiconductor node at a time when process technology is providing less bang for the buck.
“It used to be the latest node was critically important,” said Dally, who also serves as Nvidia’s vice president of R&D. “When Dennard scaling was in effect, if you were a node behind you were down a factor of three and basically screwed,” he said.
“Now the difference between 28 and 20 nm is probably like 20 to 25 percent,” Dally said. “That means to me process doesn't matter that much anymore, so if we are clever about architecture and circuit design, we can make up for the fact that we have competitors that are a node ahead,” he said referring to archrival Intel.