R400 weighs in at 200 million transistors?
According to this press release from Synopsys, a leading provider of IC design and testing software who can now add ATI Research to their list of customers, ATI's next-generation GPU will weigh in at about 200 million transistors. Synopsys' press release also seems to confirm that this next-generation GPU, which I'd assume is R400, will use a 0.13-micron manufacturing process.
ATI's visual processing unit (VPU) has more than 200 million transistors of digital logic. A design of this size and complexity requires not only extremely high stuck-at fault coverage, but also thorough testing for delay-related defects, the preponderant defect type in 0.13 micron process geometries and below. Using basic scan methods, excellent delay test requires up to 6X more tester time than required for stuck-at faults, which already is at an unacceptable cost of test.
With 65 million more transistors than NVIDIA's current NV35 GPU, and 80 million more than R350, ATI's next-generation GPU certainly sounds ambitious. If ATI is only just teaming up with Synopsys, I'd imagine that the R400 is probably a little ways off, too.