Sonnet Technologies, Inc. found itself the subject of scrutiny last week after retailer Other World Computing (OWC) alleged the company had manufactured PowerPC G3-based CPU upgrades using processors rated at lower speeds than the speed of the upgrade itself. In an interview with MacCentral yesterday, Sonnet vice president of marketing Karl Seppala provided extensive details about what happened. The company followed up by posting an updated Frequently Asked Questions (FAQ) list to its Web site.
In the FAQ, Sonnet explains in detail why some of the upgrades it sells contain CPU chips that don’t match the speed of the upgrade itself. The company relates information also provided to MacCentral by Seppala yesterday involving the speed of the processor as it relates to the operating temperature of the chip.
“Processors have an inverse linear relationship between operating temperature and speed with a factor of 0.85 MHz per degree Celsius,” said Sonnet. “In the case of a 500 MHz G3 Crescendo card, we have qualified two processors. One is a 65°C G3 500 (designated by an “A” in front of the 500 in the part number), and the other is a 105°C G3 466 (by a “C” before the 466). 466Mhz + (105°C-65°C) x 0.85MHz/°C = 500MHz at 65°C. There is no compromise in chip life, reliability or performance, and except for the number stamped on top, there is no difference between these chips.”
Sonnet also tackles the issue of why certain processors have been restamped with much lower speed ratings that they’re actually capable of working at — an issue that’s also come to the fore after certain chips used it some of the company’s 450MHz upgrades were seen to have 333MHz markings on them.
“At times, chip manufacturers have contracts to supply low-speed parts for extended periods, even after it is no longer cost effective to continue making the relatively slow parts. It is common practice in these cases to place the obsolete part’s marking on a higher-speed part to fill the contract and to avoid any pricing conflicts in the market,” said Sonnet.
The company then provided specific details explaining what happened in the case of the upgrades in question. “Sonnet purchased [the G3 chips] with the information provided by the manufacturer that they were 450MHz processors. Sonnet waived the time and expense associated with remarking them again as 450MHz. On close inspection, the original part number can be seen, screened over on the surface of the chip.”
A photo used in yesterday’s coverage illustrates Sonnet’s claim. For a more detailed explanation read the FAQ