It seems the errata error found in AMD's Quad Core Opteron ("Barcelona") did indeed cause a delay in shipments, forcing the company to revise the design and delay volume shipment from this quarter until Q2 of 2008.
Semiconductors are prone to errata errors, which only manifest when the chip is made. They are usually minor and only triggered under specific circumstances, and can often be fixed in the BIOS (define) or with a software fix.
"With this one, we created a software workaround but there was a performance penalty. To fix it the right way required a new revision in silicon," explained Steve Demski, product marketing manager for Opteron at AMD.
Demski said that the errata bug affects highly threaded applications due to a problem in translation between the L2 and L3 cache on the chip, which resulted in data being overwritten. The results could cause computers to hang. Quad Core Opteron was getting into some customers' hands but the error had to this point only been seen in lab tests.
AMD had originally said there was no delay in its shipping plans, but Demski said the errata problem did force the company to delay ramping production. "We were hoping to ramp production by now," he said. Now, the plan is to begin production of updated Quad Core Opterons in the first quarter of 2008 and send them to customers for testing, and barring any problems, begin mass production in Q2 2008.
The decision, as it turns out, wasn't entirely AMD's. "Our tier one OEMs didn't want to go into mass production and risk getting this out into tens of thousands of users of hands," said Demski. AMD is still selling Quad Core Opteron on a deal by deal basis to major customers, evaluating software in the environment of the customer as they go.
He added that customers that have received Barcelona already have said they are happy with what they received and are not going to wait for the new one. This includes the Sun supercomputer project with the University of Texas/Texas Advanced Computing Center (TACC), which uses the Quad Core Opteron in the massive arrays of blades to power the supercomputer.
James Staten, a senior analyst with Forrester Research, said the inventory supply situation with system builders is so thin that he would not be surprised if they pushed back on AMD. "System manufacturer's inventory system has changed quite a bit. They try to keep a minimum amount on hand, some times just one to three days' worth," he told InternetNews.com.
Often times problems like errata are not found by the chip makers but system manufacturers, and they will tell the vendor to shop shipping because "they don't want to be stuck with the inventory, nor do they want their rather lengthy inventory process to be stopped for one delay," he said.