Chipguy:
With your holier than thou posts, you consistently make statements that are not backed up by facts. When I call you on them, you change the argument. YOu are the one who stated that the Vdd voltage is set top the minimum. Now you claim that it is set to the minimum plus a guard band.
You state that subthreshold leakage goes up exponentially by temperature forgetting the facts that one, a 30W TDP rise causes the temperature on a good HSF to go up by 6-8K. That increase is minimal wrt 342K worst case case temperature. THat when you take into account the typical K4 and K5 constants in the equation you have, change the results by very small amounts compared to the endpoint values. And since the worst case temperatures don't change, cause zero change wrt AMD's TDP.
You also imply that AMD's processes do not improve over time. You do not take into account the part of AMD designer's and engineer's arguments with facts to back them up, speed up the transistors within a process over time. That a process that generated a 2.6GHz DC Opteron 95W worst case TDP in Q4 of last year can't be sped up at all by Q4 of this year. Others say its quite possible with the planned 4 transistor improvements this year to get the 30% speed increase to 3.4GHz. Some even allowing the worst case TDP to go up to 125W to get there.
No, in your infinite wisdom, AMD just can't improve their process at all. Niether can IBM. But, Intel can improve theirs by leaps and bounds. But Itanium didn't improve more than 5-7% in speed over three years. P4 didn't improve more than 15% in speed over two years and that included two process shrinks. P-M didn't improve more than 13% in speed over two years including two process shrinks. Perhaps it is Intel that can't improve much and you want to think that AMD and IBM are stuck in the same position. Perhaps their different systems and philosophies allow them to do much better. Their history so far has proven you wrong on many counts.
I didn't miss the fact of a guard band, but you forgot to state it. You forgot that temperature isn't a factor when using AMD's worst case TDPs. You forget that processes improve over time. Most with a clue remember those things. Part of knowing is what must not be included, what can be ignored and what must be included. That is the knowledge you lack in these discussions. And that is more crucial than knowing facts and figures.
Thus you may know something about chip design, but can't apply that knowledge to other aspects of the business. Many of your on high pronouncements in the past have proven incorrect either because you ignored crucial information or placed a constraint that was illusionary.
Yes I do speculate. You have to because so much of the needed information is not available publically. And because that requires stating the rationale behind that speculation, the posts do get long. The problem is that when I don't include it, people complain and ask how I got that. So I err on saying more.
Pete
AI
