Originally posted by: pm
Originally posted by: BrownTown
From what I've read about Intel's process for the 45nm node it sounds like its gonna be very different than their last few revisions. They claim its the most revolutionary process since the 1960's. Anyways, whether or not it works could really make or break Intel in 2008.
I have been working with the 45nm Intel process and it certainly is a departure in a number of signifcant ways from previous process technologies although I'm not sure if I'd characterize it as the biggest change since the 60's. I also don't know if it will "make or break Intel" - it seems unlikely that anyone would let the company be put in a situation where this is the case - and it also remains to be seen what everyone else is going to do on 45nm. But, yeah, I agree with you fundamentally... 45nm is going to be very different.
Originally posted by: Viditor
I wouldn't be so sure...just because Intel came out with the process sooner, doesn't mean they had those cost advantages from the smaller die right away. It's most likely that initial yields (at least the first 2 turns...6 months) had very poor yields (this is SOP). Remember that Intel absolutely HAD to convert when they did because they were about to hit a speed wall with Northwood.
Your point on SOI is quite valid though...
All in all, I'd bet (don't know for sure) that Intel's 90nm transition (and probably their 65nm transition) will create chips that are more expensive than their previos nodes...at least for the first 6-9 months.
I'm not sure that I would say that "very poor yields" initially is SOP - at least not at Intel, nor any other high volume manufacturer. Typically, a process is not "deployed" until the yields hit a certain internal goal and knowing this number, I don't think that anyone would ever declare it to be "very poor". Often yield is usually a function of speed or leakage... so by pulling back on speed, you can improve yield. So if your newly deployed process is yielding poorly, the first thing that takes the hit is speed bin. This is not always the case, but it's very common.
The process is usually pretty thoroughly checked out well in advance of shipping - bear in mind that parts sample on a new process years before that process is relied upon for HVM - for example, we are seeing 45nm working IC's today years ahead of their release. Back-end validation (all the stuff that happens between A0 tape-out and final release) takes many quarters... there is plenty of time to tweak yields. A product will not release unless yields are above a set goal - release will be delayed if this is a concern. Normally a part that doesn't yield well is also far more likely to have reliability problems in the field - no one in high-volume manufacturing wants to take a hit with customers (either OEM's or end customers) for high failure rates in the field. So, to summarize, I disagree that "very poor yields" is standard operating procedure on products shipping on a new process.
As far as the discussion of who's process is lower power... you need to, as several people pointed out - compare apples to apples. Comparing microprocessor TDP is not the way to do this. The way that people should be doing this comparison is to pull the trade journal articles (IEEE IEDM articles) for the years when companies are disclosing process information and then look and see what Intel and AMD have for Ion/Ioff ratios for NMOS and PMOS FETs. To my recollection AMD does not usually disclose numbers at this conference, but with the collaboration between IBM and AMD, the IBM numbers should work as a general estimate. I don't have the time, or the motivation to do this, but arguing TDP definitions vs. microarchitectures is not the way to do it.
Ion/Ioff - the ratio of how much current the transistor can source when it's supposed to be on, vs. the amount of current a transistor leaks when it's supposed to be off - is a very good benchmark to compare because leakage and transistor speed usually go hand in hand on a given process at a given company (so you can get great power numbers if you are willing to sacrifice speed bins), but the ratio usually has a "sweet spot" that can be used as a benchmark against other companies.