http://www.digitimes.com/bits_chips/a20080704PD210.html
Nvidia contract makers in Taiwan low-key over defective chip reports
Ingrid Lee, Taipei; Steve Shen, DIGITIMES [Friday 4 July 2008]
Nvidia's Taiwan-based graphics chip contract makers are being low-key after the US chip designer informed investors on July 3 that will take a charge of US$150-$200 million related to expenses stemming from issues discovered with die/packaging materials used in previous generation notebook products.
With Nvidia indicating that the problem is due to the packaging material used with some of its chips, which was compounded by the thermal design of some notebooks, industry sources in Taiwan believe the problem is most likely related to either the solder bumping process used by one (or more) of Nvidia's manufacturing partners or the company's PCB substrate supplier(s).
Sources at foreign institutional investors in Taiwan indicated that the defective products were Nvidia Geforce 8500M-series graphics chips launched in 2007, and that the problem was caused by related bump processing. Taiwan Semiconductor Manufacturing Company (TSMC), Advanced Semiconductor Engineering (ASE) and Siliconware Precision Industrial (SPIL) all provide bump processing services to Nvidia.
When ask for comment by Digitimes TSMC declined citing client confidentiality, while ASE and SPIL both claimed to know nothing about the issue because the defective chips are older generation products.
On the other hand, some industry insiders believe the problem might have been caused by PCB substrates supplied by Nay Ya Print Circuit Board (NPC) or Phoenix Precision Technology (PPT).
The sources speculated that the problem could be that the green paint used by NPC in PCB production might have lower than expected heat resistance, or that the adhesiveness of ABF (Ajinomoto Build-up Film)-based substrates produced by PPT might not be strong enough.
However, NPC and PPT both refuted the speculation saying their PCBs are not the components at fault.
