X-bit Labs reports AMD failed to meet demand for Radeon HD 5000 series graphics cards due to continuing issues with the yields of TSMC's 40nm process:
Even though Taiwan Semiconductor Manufacturing Company claims that the yields on its most advanced 40nm node are high enough for mass production of advanced chips, actual designers and suppliers of graphics processing units still seem to have problems.
"We have had very good demand for our Radeon HD 5700-series and 5800-series. [...] We could not meet all our demand in the third quarter of this year on the Radeon HD 5800- and 5700-series. But the overall situation was getting better in Q3," said Matt Skynner, corporate vice president and general manager of GPU division at AMD in an interview with X-bit-labs.