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Of course, everything new will be 32nm or smaller. There's no way back, because the performance would drop.
I deplore this renaming and remarketing to excess. There are 4 basic states in any cpu cycle. Address instruction, Read instruction, decode, & execute. There is a limit to what read ahead and cache can do.
The fab size (32nm vs 45nm) feeds back into reduced capacitance, which greatly lessens current consumed, and also increases speed. 2 formulas that matter are:
0.5 x C x Ve2 for the energy stored in a capacitor (C in farads, answer in joules)
V x C x Fe2 (or something) for the energy expenditure clocking a capacitor. Gates for your standard mosfet taking any power can be 15pF (15e-12F). It's not hard to see massive energy consumption in a cpu this way.
Of course, everything new will be 32nm or smaller. There's no way back, because the performance would drop.
The fab size (32nm vs 45nm) feeds back into reduced capacitance, which greatly lessens current consumed, and also increases speed. 2 formulas that matter are:
0.5 x C x Ve2 for the energy stored in a capacitor (C in farads, answer in joules)
V x C x Fe2 (or something) for the energy expenditure clocking a capacitor. Gates for your standard mosfet taking any power can be 15pF (15e-12F). It's not hard to see massive energy consumption in a cpu this way.
Correct me if I'm wrong, but doesnt dropping fab sizes only have a real impact on power consumption, not speed.
Unless you are count the power consumption allowing more transitors, or higher clocks, but even they can have little effect. See 130nm P4 'northwood' vs 90nm P4 'Prescott', even with a dieshrink there was very little performance gains (but to be totally honest, it wasnt just a dieshink, there were various changes)
Quote:
Originally Posted by business_kid
I deplore this renaming and remarketing to excess. There are 4 basic states in any cpu cycle. Address instruction, Read instruction, decode, & execute. There is a limit to what read ahead and cache can do.
Which renaming?
I got used to marketoids renaming chips years ago. Pentium Pro, opps, that flopped, lets repackage and rebadge it as Pentium II....
Again, I look for FSB freq and cache size, which I think are most important nowadays. The CPU freq is less important, because CPUs are so powerful now that it is more important to get data to them fast, so they can process it. This is where cache size and FSB come in. When I buy a processor I look first at the highest FSB the mobo supports, then choose the one with the highest cache size, as long as it is affordable. Then, of course, I check the mobo manual or online info to make sure it actually supports that CPU.
Correct me if I'm wrong, but doesnt dropping fab sizes only have a real impact on power consumption, not speed.
More or less. It also feeds into faster propagation times (off/on switching) but this isn't often translated into a noticeably higher speed
Quote:
Originally Posted by cascade9
Unless you are count the power consumption allowing more transitors, or higher clocks, but even they can have little effect. See 130nm P4 'northwood' vs 90nm P4 'Prescott', even with a dieshrink there was very little performance gains (but to be totally honest, it wasnt just a dieshink, there were various changes)
Which renaming?
I got used to marketoids renaming chips years ago. Pentium Pro, opps, that flopped, lets repackage and rebadge it as Pentium II....
I had no specific renaming in mind, although I knew some went on. It's the things like 'hypertransport,' a marketing name for what is basically an electronic design option which transpires to be a bit faster than what they were doing previously. AMD is no less guilty here, btw. I have had my head in the sand as far as all this stuff is concerned for years, studiously ignoring marketing 'data sheets' and sales tripe. I haven't seen a technical data sheet for any modern cpu. They are not issued because the explode these marketing myths.
The Pentium 4 had a "532" mhz hypertransport but it's notional width was 8 bits, so when you boiled it down, it was switching 32 bits at 532/4 = 133 Mhz.
My laptop has a "667" mhz bus. We're 64 bits wide, and I believe a divide by 4 is applicable again, which is in fact 166.75 Mhz bus speed. I see 1333 Mhz stuff out there now. I refuse to believe that speeds have doubled, until someone who sees through all the b.s. tells me so. Marketing hype has doubled.
There are several good reasons for this skepticism. Without getting overly technical, take track length. The address/read cycles are where the ram is read. On one clock cycle, the address will be good by the end of it; on the next, ideally, the data will be good, and can be read back. At 1333Mhz, electricity can only travel a maximum of 22.5cm (3e8 / 1.333e9), so distance across the board becomes a significant delay factor.
Back in the 80s, I worked temporarily in Amdahl repairing machinery that made their cpu units for the huge mainframes they built. One of my pains in the neck was a clock wire machine, which gave out wire of a specific length. The clocks (~125Mhz) all had to be wired with wires of specified length (+/- 0.1 in. or 25mm). The next model (after they fired me) was water cooled.
These had 6-9 boards of 11 x 11 SMT ECL logic chips with huge cooling towers, and ran from a 5V 400A(!) power supply. Fab does make a difference!
Ok, it has been a while since you checked all the marketoid junk hasnt it? (no offence intended).
AFAIK, Intel has never used hypertransport, QPI is the current Intel equivilent to hypertransport.
You are right about the P4 FSB BTW. Though there were also 400MHz, 800MHz and 1066MHz P4 FSB models. I cant recall what the (real) memory speed is on the 1066MHz FSB models (they might be using DDR2, see below), but for the 400, 533 and 800MHz models the 'real' memory speed is 1/4 of the FSB (due to quad-pumping).
Since hypertransport and QPI, FSB doesnt really exist. When you see '1333MHz' its the memory speed. BTW, 1333MHz is almost low now, 1600MHz is more common, and 2400MHz is now on the shelves. But that number, like all DDR numbers, is semi-marketing. The real core speeds of memory hasnt changed much in years now....
DDR1 200-400MHz divide by 2. So 'DDR200' has a real core speed of 100MHz, and the most common DDR400 is 200MHz real core speed. BTW, DDR1 got at least as high as 550 (275MHz) but its rare to find DDR RAM with higher speeds than DDR-400.
DDR2 400-1066MHz divide by 4 (same as DDR1, but with a x2 bus clock multiplier). So DDR2-400 is back to a real core speed of 100MHz, DDR2-800 is 200MHZ, DDR2-1066 is 266MHz. DDR2 went at least as high as 1200, but again, thats rare.
DDR3 800-2400MHz divide by 8 (same as DDR1 but with a x4 bus clock multiplier). DDR3-800 is again 100MHZ real core speed, the most common DDR3-1600 is 200MHz and the fastest you can get now is DDR3-2400, 300MHZ.
Speeds....difficult to say that they have doubled. Bandwidth sure has, but bandwidth does not always equal speed....
As for the technical data sheets, yeah, they did start dumbing them down years ago. Yes, I agree, it was in part because the technical data sheets would have made the marketoids look a bit silly. Using the same 130nm P4 'Northwood' vs 90nm P4 'Prescott example I used above, you can see why they didnt release a full data sheet-
Northwood- 8KB L1, 512K L2 cache.
Prescott- 16KB L1, 1024KB L2 cache. (FSB varies, but you can get the same FSB with Prescott as with Northwood).
So if you just check the 'basic' specs, Presscott looks like a clear winner. But when you start looking closer, its not so clear-
If intel had of put all that into a technical data sheet, it would have been much more clear exactly what differences there is between the Northwood and Prescott CPUs. Which is nowhere near what you would expect if you just checked the basic specs, which is what the marketoids were pushing.
Motherboard brand and chipset was a random choice. DDR2-1066 support is from the intergrated memory controller (though it needs a comptible chipset to work of course) and is AM2+ only. Well, it might be true with AM3 as well, I've never checked.
I'm putting a "Solved" on this one, because we are pretty much in agreement. We're actually a long way from where we started, but who cares? It had been an interesting and indeed educational discussion of cpus in general, and I thank you guys for condensing your hours wasted assessing Intel and AMD's Panglossian marketoid blurb so astutely. You have reinforced my resolve not to waste similar time myself, and verified my decision to desist in the first place. (Pangloss, btw, was a hopeless optimist in Candide- "This is the best of all possible worlds").
I ran an i586 for years, doing everything I do today and more, and although I felt the need for an upgrade, I didn't benefit much from it when it came. I remember what people did on CP/M (Z80@4Mhz, 64k of ram). These days I see people doing pretty much everything with little arm based netbooks and a tiny ssd. The OLPC is hugely impressive for what it is.I'll read the marketing factoids when I am specifying a server, or a gaming machine.
I'm putting a "Solved" on this one, because we are pretty much in agreement. We're actually a long way from where we started, but who cares? It had been an interesting and indeed educational discussion of cpus in general, and I thank you guys for condensing your hours wasted assessing Intel and AMD's Panglossian marketoid blurb so astutely.
Less hours wasted here than you might guess.
Glad is wasnt totally boring, or you're polite enough to overlook the boredom factor.
Quote:
Originally Posted by business_kid
You have reinforced my resolve not to waste similar time myself, and verified my decision to desist in the first place. (Pangloss, btw, was a hopeless optimist in Candide- "This is the best of all possible worlds").
Voltaire, for a second there I was thinking I had missed something in my 'not so classical as it could have been' education. I think somebody was telling me to read Candide years ago, maybe I should give it a try.
Quote:
Originally Posted by business_kid
I'll read the marketing factoids when I am specifying a server, or a gaming machine.
I wouldnt even bother to read the marketing even then. Maybe for servers, but not for gaming machines. "Look out, dont step in the marketing" LOL. Its always the same sort of stuff, 'we are wonderful, setup XYZ is so great that everybody wants it', blah blah, yada yada.
For gaming machines, its easier just to check you budget, then get a few different sourced benhmarks. Aside from 'dodgy' hardware a few different benchmarks and soem thinking time is all you need for gaming setups. (dodgy hardware, intel and AMD have both done it, though intels done it worse than AMD. Nobody is going to put "we were pushed to get this hardware out the door and it could have issues" in the marketing blurb, so its besides the point anyway....
Voltaire, for a second there I was thinking I had missed something in my 'not so classical as it could have been' education. I think somebody was telling me to read Candide years ago, maybe I should give it a try.
I wouldn't recommend it. I read the plot summary and it sounds boring, pointless, and stupid. I understand why people fall asleep during the opera. The source of the reference is S.J Gould. If he taught English writing instead of evolution (He's one of the Punctuated Equilibrium variety of evolutionists) his pupils would be prize winners. As it is, the talent is wasted.
Quote:
Originally Posted by cascade9
Nobody is going to put "we were pushed to get this hardware out the door and it could have issues" in the marketing blurb, so its besides the point anyway....
And the fact is (And I have been in R & D) every project goes out with a blowtorch pointing at someone's behind. The only things that varies are who is holding the torch, and how much flesh has been toasted. The safe, sensible thing is done - and people stop thinking of consequences.
EDIT: Now that I think about it, everyone rewrote that or bits of it, and did it better than the original guy. Voltaire certainly did, and it was spun into 'the optimist.'
Last edited by business_kid; 05-26-2011 at 02:35 PM.
I wouldn't recommend it. I read the plot summary and it sounds boring, pointless, and stupid. I understand why people fall asleep during the opera. The source of the reference is S.J Gould. If he taught English writing instead of evolution (He's one of the Punctuated Equilibrium variety of evolutionists) his pupils would be prize winners. As it is, the talent is wasted.
EDIT: Now that I think about it, everyone rewrote that or bits of it, and did it better than the original guy. Voltaire certainly did, and it was spun into 'the optimist.'
Punctuated Equilibrium? I barely ran into that doing evolutionary anthropology. Then again, my lecturers were of the phyletic gradualism school, maybe if they were into punctuated equilibrium we would have heard more about it.
I'll take the boring pintless and stupid warning, I'll take it under advisment. Voltaire is a satirical polemicist, so I can se where an overview of one of his plays could sound pretty awful. If its as bad as advertised, I'll drop it and read something else. Thats if I can find a copy of Candide in the library, I dont like reading non-technical documents from a scree. n
Quote:
Originally Posted by business_kid
And the fact is (And I have been in R & D) every project goes out with a blowtorch pointing at someone's behind. The only things that varies are who is holding the torch, and how much flesh has been toasted. The safe, sensible thing is done - and people stop thinking of consequences.
Thats true, every project has somebodys head on the chopping block (that is the image I get after Voltaire has been discussed LOL). With 'desktop' computers it seems that sometimes the blowtorch is aimed at the motherboard (etc.) of the user! Its worst when the company is under pressure- intel is particularly bad there, with a litany of overheating and unreliable CPUs, but almost everyone in x86 CPUs or GPUs has done it- Intel, AMD, Cyrix, 3DFX, nVidia, ATI......
I apologize if this seems like "hijacking", but as I'm reading through this thread, the impression I get is along the lines of "don't believe any specs that you read online", because chances are that they're always leaving something out to deceive you. Great, so when I (maybe) do my own desktop build, it's gonna be even harder to look up specs for a decent machine because I'll have to look up specs far beyond what is listed on the site or whatever (and WTF am I supposed to find this extra info??).
I'm clearly a dumbass for having not taken into account things like "double/quad-pumping" (taking twice/four times the amount of clock cycles to get data across the FSB), etc.
I dont totally agree with business_kid, I'm a bit less harsh.
You can belive the specs, noone who wants to stay in business tells outright lies about them. When Intel say 'P4 Prescott 1MB of L2 cache' it is the truth. They just left out the (probable) fact that the L2 cache on Prescott is in some ways slower than it was with Northwood. You can put that down to 'marketing' or if you want to be charitable you can say that nobody really cares so intel just omitted to tell anybody...
Where it gets nasiter is when you start looking at the marketing factoids. I'l give you an example-
Quote:
It looks like Intel is starting to take graphics seriously. It promises that G45 chipset will be three times faster than G33.
Fudzilla (and most other sites) have added this bit-
Quote:
When Intel makes this kind of statement this means it will be three times faster in 3Dmark06.
Which is NOT what the marketoid fact sheet says. It just says "Targeting 3X 3D performance of the intel G33 Express Chipset"
(unless there is some 'in 3D mark' disclaimer in the fine print down the bottom of the graphics intel made, I cant find a better copy where the text is readable). It actually is about 3x faster in 3Dmark-
But that doesnt equate to 3x faster performance in games, not even close. Scroll down on the pcstats link and you will see that '3x faster' becomes 'less than 2x faster' in performance for at least one game, and I'd suspect that would be similar over many games.
So if you just check the marketing junk, you could well think that the G45 will give you framerates 3x faster than G33, which just isnt true.
There is also the way that people mislead themselves- I've heard many people talking about upgrading from a SATAI (1.5Gbit/s) to a motherboard/controller with SATAII (3Gbit/s) or SATAIII (6Gbit/s) support 'because my HDD will be 2-4times faster". Nope, thats not true, mechanical HDDs are JUST starting to saturate SATAI bandwidth. No mechanical SATA HDD will get close to filling SATAII bandwidth, let alone SATAIII. About the only time that you extra bandwidth will make a difference is when you are copying a file over that will fit into the HDD cache.
Worring about 'hidden' specs isnt really worth it. Using a similar example to the P4 L2 cache above but something that is current, really not that many people even care that there are minor differences in latency between versions of the i7 (and i3/i5 as well for that matter). For the engineers working on CPUs, it matter, for an end user its at best a point of intrest.
There is info around on minor, mainly esoteric differences like the cache latency, but even finding it can be a major quest. Then you have to decide if the info is even trustable...
Dont worry about it, if you ever do go to biuld your own computer avoid the Intel, AMD, ATI, nVidia, WD, Samsung, Seagate, Hitachi, etc. marketing, and trust decent benchmarking, user reviews, even semi-random forum posts over marketing blurbs.
I wouldnt call you a 'dumbass' for not paying attention to pumping. I know people who spec and build computer who dont know anything about it, and they %&#$%&$ should know.
As for "hijacking", I wouldnt worry about it. From the posts I've sen by business_kid, they are more than able to tell both of us to stop mucking up the thread, and do it a polite way as well. Its marked 'solved' anyway, even though I'm still at a loss at to why there was that huge jump in performance.
Honestly, if I'm looking at computer hardware at all, I try to look up the specifics. For example, if I'm looking at a video card/GPU, I'll look for stuff like the clock speed(s, if applicable, e.g. shader vs. core clock, etc.), memory type/amount, etc.…I wouldn't trust something like "3x faster than the previous model" right away without doing a bit of technical research first. Most of what I was concerned about was whether I do enough "looking" to really try to find a decent piece of hardware.
WRT the whole SATA thing: that actually makes a lot of sense; a mechanical HDD's speed is mostly dependent on both its platter RPM and the actual transfer rate (AFAIK). If the transfer rate is blazing fast, but the platters can only spin so fast (and hence data can only be put into the HDD cache so fast), then you're not going to be able to use all that bandwidth.
Quote:
Worring about 'hidden' specs isnt really worth it. Using a similar example to the P4 L2 cache above but something that is current, really not that many people even care that there are minor differences in latency between versions of the i7 (and i3/i5 as well for that matter). For the engineers working on CPUs, it matter, for an end user its at best a point of intrest.
In other words, stuff like pumping/cache latency only really matters to either someone who wants to squeeze every last clock cycle out of their CPU/memory (), or to someone who's designing (or helping to design) a CPU themselves, or something…?
Well, I suppose I can rest relatively easy now. I guess it just goes to show that I've still probably got plenty to learn about the specifics.
Honestly, if I'm looking at computer hardware at all, I try to look up the specifics. For example, if I'm looking at a video card/GPU, I'll look for stuff like the clock speed(s, if applicable, e.g. shader vs. core clock, etc.), memory type/amount, etc.…I wouldn't trust something like "3x faster than the previous model" right away without doing a bit of technical research first. Most of what I was concerned about was whether I do enough "looking" to really try to find a decent piece of hardware.
No problem, I'm glad it helped.
There is always an element of luck in hardware IMO. Back when Socket A was current, I would never have guessed that 'low end' motherboards with SiS chipsets would outlast many of teh more 'top end' socket A motherboards with VIA chipsets. But from my experience, that it seems to be the case that (for socket a at least) cheap-assed SiS chipset can last a long time, longer than the average VIA chipset.
The long term lifespan, which I consider to be _VERY_ important, is at best an educated guess though.
Aside from lifespan, you really wont notice much difference between chipsets/motherboards/CPUs/RAM of the same type. Boards using chipset 'XXXX' with CPU 'YYYY' and RAM 'ZZZZ' are normally in an performance envolope of 1-2.5% in general (normally all parts of that type, no matter the manufacturer, will be within 1-2.5%). Aside from things like 'factory OC' models, the same is true of video cards.
You've also got to consider 'what do you need it for'. The number of times I've seen people buy expensive 'gaming' video cards because of flawed logic like 'it costs twice as much its got to be twice as good'. They would have been a lot better off getting a 'normal' dekstop card and spending the extra money on a SSD.
Mismatched tasks and hardware is not only a waste of money, it can affect lifespan of the system, due to things like 'gaming' cards having higher power requirements and more heat output. That sort of mismatching is easy to avoid as long as you dont fall into the marketing trap, and think about what you would be using the computer for.
Quote:
Originally Posted by MrCode
In other words, stuff like pumping/cache latency only really matters to either someone who wants to squeeze every last clock cycle out of their CPU/memory (), or to someone who's designing (or helping to design) a CPU themselves, or something…?
Yeah, you cant change the pumping, or latency. CPU cache latency only really matter to people who are designing CPUs, and its not really worth worring about...any major changes in latency should be shown up by checking benchmarks. Pumping and bus clock multiplier (in particular for DDR versions) can matter, but the only people who worry about it are hardcore overclockers.
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