Originally by ddtlm
Well there's certainly no desperation involved. My position is that noone knows what IBM is working on besides "next generation PPC", which could be anything from 90nm 970's to referring to the Power5.
The Power 5 is NOT a PowerPC. If IBM says it's working on the next generation of the PowerPC, it is NOT referring to the Power5.
If IBM shrinks the 970 to 90nm and uses much of the Power5 for the "980", there is no reason that they would have had to done anything 980-specific when the 130nm 970 was being developed (the original claim), or really even by now.
The 970 is a 'spin off' of the Power4 BUT, it is more than just a cut down version. Power4's, to the best of my knowledge, does NOT support HT links. Power4 does not support Altivec. It would be foolish of IBM to not build upon the 970 when they were working another 'lite' version of the Power5.
Peter Sandon, the chief architect of the 970 has already admitted they are looking into revising Altivec in future revisions. This is just one more clue that there are future PPCs in development.
the 130nm Power5 not coming out till late 2004 at the earliest, I'd be very surprised if a "980" was available before that, especially at a different feature size (than the Power5). I'm still thinking a very realistic and achievable schedule would be to have 90nm PPC970's for the summer of '04, and replace them the summer of '05
It's entirely possible that there will be .09 micron 970s next summer. This is really what I think also. That doesn't mean that IBM isn't working on the next generation of the PPC. And I'm not talking about a die shrunk 970, I'm talking about the next major revision of the PPC architecture.
Of course they are, but derivative chips aren't being worked on separately as far ahead of time. To use your example of Sun, they probably weren't developing the US4 when the US3 was pre-release... cause they are based on the same core.
I'm fairly certain the US 4 was being worked on when along with the US 3. The fact that one processor is based off the other doesn't prove that they can't be designed in parallel. US 4 will likely be dual core. It probably isn't feasable to make dual core US 3's on todays processes, but that doesn't mean that Sun doesn't say "this is what we are trying to accomplish for the US 3, but keep in mind that US 4 is gonna be 2 of these cores and lets work on these revisions and refinements too"
I think that they were probably reffering to the Power5, but a 90nm 970 would technically count.
Why would IBM talk up Power5 processor development when talking about Macs? Do you really, I mean honestly think that IBM reps would talk about the development of the Power5 at WWDC, or in interviews about the 970 in the Macintosh? Don't you think that when an IBM rep steps on the stage at WWDC and says 'we have a fantastic road map for you', they mean the roadmap for future PowerPCs and not the roadmap for future Power processors, which they might spin off a 'lite' hack version?
Its all marketing driven. Just because upgraded G4's weren't hailed as revolutionary doesn't mean upgraded G5's won't be.
Yes, the term 'generation' is somewhat a marketing tool, but it's also a description of a processor that is essentially new (though based off previous work). The Power5 is a new generation of Power processor over the Power4. The 604e (though it had an additional FPU and other changes) was essentially just another 604. The revisions of the G4 were just incremental revisions of the G4 architecture. They weren't what anyone would call new generations of the PowerPC processor line. What I mentioned before was, Apple, IBM, and Motorola don't have a history of calling something as trivial as a die shrink a new generation. It's never happened before and if you assume that's what they mean now, you'd have to accept that IBM and Apple are treating this processor differently than any other PowerPC processor.
SOI, as you said. Should cut a lot of heat out, and the other features that add performance per clock cycle seem to help the performance/heat ratio a lot.
But SOI, as I stated, doesn't nescessarily change the typical to max thermal ratio. I don't know if it would, I don't know if it wouldn't. I would imagine that the architecture of the processor would have more to do with this.
You started comparing typical figures to max figures and concluded the G5 uses less power.
No I didn't. I compared typical 970 wattage, to typical Athlon wattage, which was very close to max Athlon wattage. I made a direct claim that typical for the 970 is less than typical for the Athlon.
I made the assertion that it is ENTIRELY POSSIBLE that the Athlon 64 would similarly have a similar typical/max wattage since it's a bulked up Athlon. I later came back with a link to stats that indicate that Athlon64 does indeed seem to have typical wattages that are very close to Max wattage. so that point is kind of moot now isn't it.
I dunno about claims that an Athlon "typical" is similar to max, because of course typical isn't defined. Is typical idle, or running a certain application? Does IBM define it the same way? Does Moto define it the same way?
don't you think that engineers in the same industry would tend to describe microprocessors in the same basic way? There is no reason to quote chip characteristics if they aren't based on some type of standard definition. I'd have to think that Typical wattage isn't based of an idle cpu. What is so "typical" about a computer that isn't allowed to process something?
Your link listing Opteron thermal power illustrates exactly what I said was true: AMD only lists one max output for the whole Opteron family. So all we know is that all current and same-family future Opterons use <= 80.6W in a worst case. As far as I know, all we know about G5's is that they "typically" generate 47W at 1.8ghz, and 18W (I think) at 1.2ghz.
Intel also quotes large blocks of CPUs at the same wattage. This isn't uncommon. This is because the chips are the same size, on the same process, and they all run at the same core voltage and amperage. Wattage is a calculated by these features. When you calculate wattage you don't factor the frequency into the equation.
If you look a the different wattages for the 970s, they coincide with different core voltages too. The 19watt 1.2 GHz part noted in last years presentation (by Peter Sandon at MPF) was a 1.1v part while the 47watt 1.8GHz part was running 1.3v.
You can look at "typical" vs max thermal powers for Athlons and speculate that a similar relationship exists for G5s,...<snip>. But the Opteron could easily be using less and the G5 could easily be using more.
but I don't have to assume the G5s max when I've already posted Typical figures for the Opteron, which indicated that the current Opterons had Typical wattages of 80.6 watts. So, I've presented Typical wattage for the Opteron, and typical wattage for the PowerPC 970 yet you say that they could easily be more or less than the published figures??
AMD's 80.6W figure applies to the whole Opteron family, and who knows how fast AMD has planned on that scaling. 80.6W might be for a 2.4ghz Opteron.
Interesting. You really think that AMD would say, 'here are the technical details of our processors, but they aren't accurate because we are ACTUALLY giving you the wattage figures from a processor that hasn't been announced yet. I have to agree with you, that's what I'd expect AMD to do also.
Assuming that's running the same voltage as a 2.0ghz model, the 2.0ghz model is already pushed down to 67W. Note that this is not an unreasonably low figure either, an Athlon on 180nm running at 1.8ghz uses a max of 68W
First off, when I provide you with a source indicating a typical wattage of 80.6, how do you assume 67watts? Where is the leap there?
Secondly... you are comparing the wattage of a .18 micron Athlon with a .13 micron Athlong 64 which is OVER 100MILLION TRANSISTORS? The Athlong 64 is MUCH larger than an Athlong. Talk about a leap.
But back to my assumptions about non-increaseing voltages. Unfortuneately, its not very likely that voltage is going to remain constant for either the G5's or the Opterons. (Your lostcircuits link nicely shows Athlon voltages changeing with clockspeed.) That 10W gap could dissapear really easily,..<snip>... The Opteron might even end up using less power.
I'm lost again.
You are arguing with the assertion that todays 970s use less power than todays opterons and your argument now is that future Opterons and 970s will likely require higher voltages on the same process and this will make a difference some day? Huh?
But hey, this is all speculation. Maybe all Opterons use 80.6W all the time (as difficult to explain as that would be), maybe the max power of a G5 is 53W at 2ghz. I don't know what the real numbers are, and I don't think you do either.
I don't happen to design chips for IBM and AMD. That doesn't prevent us from using the data available to make reasonable assumptions. It is NOT unreasonable to assume that 970s are cooler chips than Opterons when the 970 is roughtly HALF the transistor count of the Opteron, the 970 operates at a lower core voltage, the 970 operates in roughly the same frequency range, the 970 is built on essentially the same process.
It would be extremely unlikely that the 970 would not run cooler than the Opteron given these facts (and yes those are facts and not assumptions).
