Replies to post #18943 on Advanced Micro Devices Inc (AMD)

[Dan3]

Re: Why - because Dan3 is declaring it more reliable?

No, because it has a lower component count, leading to fewer opportunities for error during manufacturing and test. Question - where are you most likely to see more failures, from similar collections of 30 complex IC components or collections of 100 complex IC components?

In fact, Itaniums reliability problems go beyond its much higher component count. The interesting thing is that, since Itanium is basically a triple core CPU, it might have had enhanced reliability (since a straightforward triple core CPU could have reduced component count, somewhat).

But HP/Intel elected to try to design a chip in which the 3 cores could concurrently execute a single process (through software scheduling) and it just hasn't been working out. For one thing, the weirdness associated with compiling code for linked triple concurrent in-order cores has proven very difficult to test for, leading to an entire generation of faulty Itaniums being shipped (the infamous 900 and 1000mhz McKinley chips). Note further that Intel wasn't able to catch the problem and it was Fujitsu's qualification process that determined that many Itanium IIs were defective.