FSB Expense and Future Machines

Posted:
in Future Apple Hardware edited January 2014
The 970 itself isn't responsible for the price spike in the Power Mac line. A portion of it is likely profit taking, but I'm also guessing that another major contributor to cost is the speedy FSB. Now assuming that the bus speed remains fixed at (an effective) half the clock of the 970, I'm expecting continued upward pricing pressure as the G5 line matures. (It's wonderful to have to think about the implications of a fast FSB, after suffering through the G4 for so long.) The promised 3GHz box will need an effective 1.5GHz bus, and obviously that's going to be expensive.



Assuming my initial thoughts are reasonable, perhaps one of our resident geniuses can help me with these questions:



An effective 1.5GHz could be achieved through a double pumped 750MHz bus, but wouldn't such a fast bus be cost prohibitive? Alternatively, it could use a quad pumped 375MHz bus, which would be cheaper but slower than what we have now. However, would such a quad pumped solution be required in order to keep costs at a reasonable level?



Perhaps most importantly, what can we expect in terms of future priceerformance? Will Apple be forced to maintain high prices on the line due to bus speed demands?

Comments

  • Reply 1 of 20
    jcgjcg Posts: 777member
    I would expect price pressures would drive the 970's down, not up. The current price is no doubt partially due to adding a premium to the low end units profit margin to help pay off R&D on the new chip set and mother board. I may be optamistic here, but I would expect an update or new low end model and price drop when Panther is released, now by year end instead of September. If I recall, IBM was going to move the 970 to a 9nm process by year end, so it might be possable that we will see PB's, and dare I say iMacs (doubtfull) using the 970's in San Francisco.
  • Reply 2 of 20
    wmfwmf Posts: 1,164member
    Quote:

    Originally posted by Big Mac

    An effective 1.5GHz could be achieved through a double pumped 750MHz bus, but wouldn't such a fast bus be cost prohibitive? Alternatively, it could use a quad pumped 375MHz bus, which would be cheaper but slower than what we have now.



    Why would quad-pumped be cheaper than double?



    Given those $1M mask costs, I don't know if Apple can afford to change their bus protocol every year.
  • Reply 3 of 20
    outsideroutsider Posts: 6,008member
    Here is a funny thing to think about, the MHz difference between the low end G5 and the high end G5 is more than the speed of the G4 it replaced. Nice.
  • Reply 4 of 20
    thttht Posts: 3,115member
    The PPC 970 bus is a serialized 32 bit wide bus (per direction) that doesn't have tight signal synching and "integrity" requirements on it. "Elastic". It's just some 32 traces plus ground, clock, etc. Probably around 40 per direction. So, there aren't that many, signals can even be sent while the preceding signal is in transit, and they can be traced over long PCB distances. It'll clock up to 750 MHz without much expense. Just look how far away the DIMM slots are in the PMG5. I don't think you'll find DIMM slots that far away from the CPU in x86 boards.



    Contrast this with the parallel Pentium 4 bus that has 64 data lines, 32 address lines, plus half again as much for ground et al for somewhere around 150+ lines to clock up to 200 MHz and clocked in sync. Apple's dual 970 system controller may even have less processor bus traces than Intel's uniprocessor system controller. Also, Intel will probably have a harder time clocking the P4 bus from 200 to 250 MHz than Apple will with the 970 bus from 500 to 750 MHz.



    By the way, Rambus has chip-to-chip bus technology with effective data rates up to 6.4 GHz!
  • Reply 5 of 20
    amorphamorph Posts: 7,112member
    Ahhhh, there's no engineering like good engineering.



    As for pricing, I'm of the opinion that the PowerMacs got squeezed into a historically narrow price bracket to make room for more and different stuff. Sure, they have a new CPU and a new board, and "perhaps the fastest ASIC in the industry" or whatever Steve said about their system controller, but strategy is always an element in pricing, and Apple likes to set price points that it intends to keep. The price slashes on the PowerMac G4 were a last-ditch response to lukewarm demand for a lukewarm product.



    I wouldn't be surprised if the PM goes all-dual before too long.
  • Reply 6 of 20
    Quote:

    Originally posted by Amorph

    Ahhhh, there's no engineering like good engineering.



    As for pricing, I'm of the opinion that the PowerMacs got squeezed into a historically narrow price bracket to make room for more and different stuff. Sure, they have a new CPU and a new board, and "perhaps the fastest ASIC in the industry" or whatever Steve said about their system controller, but strategy is always an element in pricing, and Apple likes to set price points that it intends to keep. The price slashes on the PowerMac G4 were a last-ditch response to lukewarm demand for a lukewarm product.



    I wouldn't be surprised if the PM goes all-dual before too long.




    I agree the price of the G4 have fallen to sell what they could. I expected the current prices (1700 to 1800 for a combo drive low end). Apple has a lot of R&D to recoup with these new chips & mobo designs.



    I also agree on the duals for the powermacs. I expect production at the plant to generate higher yields with the amount of automation that IBM uses. Unlike the horror stories of moto fab sites.
  • Reply 7 of 20
    big macbig mac Posts: 480member
    Thank you so much for all of the great information. I'm not an engineer, so it's wonderful that I can rely on those who are. I feel much better now about the future of affordable G5s.
  • Reply 8 of 20
    eugeneeugene Posts: 8,254member
    Quote:

    Originally posted by THT

    I don't think you'll find DIMM slots that far away from the CPU in x86 boards.







    This is a problem present on my Asus P4PE. It has three PC2700 capable DIMM slots, two of the slots share one bank, so in reality it's more like two slots. Running faster memory compounds the problem...along with running multiple DIMMs.
  • Reply 9 of 20
    akumulatorakumulator Posts: 1,111member
    Quote:

    Originally posted by Amorph

    Ahhhh, there's no engineering like good engineering.



    As for pricing, I'm of the opinion that the PowerMacs got squeezed into a historically narrow price bracket to make room for more and different stuff. Sure, they have a new CPU and a new board, and "perhaps the fastest ASIC in the industry" or whatever Steve said about their system controller, but strategy is always an element in pricing, and Apple likes to set price points that it intends to keep. The price slashes on the PowerMac G4 were a last-ditch response to lukewarm demand for a lukewarm product.



    I wouldn't be surprised if the PM goes all-dual before too long.




    I agree. I think the only reason Apple initially released the high end machine with dual processors and the others single is to sell the high end model. The next update will definately be all dual.
  • Reply 10 of 20
    flounderflounder Posts: 2,674member
    Quote:

    Originally posted by Akumulator

    I agree. I think the only reason Apple initially released the high end machine with dual processors and the others single is to sell the high end model. The next update will definately be all dual.



    My guess is the next rev will be single on the bottom, dual on the mid and high.
  • Reply 11 of 20
    blestblest Posts: 24member
    ok ok. i started reading this thread and the first few statments startled me. Why are we to assume taht just because the processor will ramp up to 3 ghz that the front side bus will have to be jumped up as well? comin from using a bunch of windows machines ive seen my fair share of front side bus ramping. the pentium 4 went from 400 to 533 to 800. but the point is it took some time for those changes to be made. It also required validated memory. it required work on the Memory controller hub to handle it all efficiently. with the front side bus they have in place already i feel that apple has time to grow into it. and maybe im wrong but from waht i understand ddr ram in its current state (not till DDR II) will top out somewhere in the 500 mhz range. so that definately wont fully feed a 1.5 ghz fsb. then since your running asynchronously youll take a performance hit. doing that would just make a faster processor and a faster fsb without the right amount of flow making the cpu have more idle states where it does nothing but wait. just look at how the pentiumm 4 was always to a degree threatened by amd. amd's athlons fsb and ram ran synchronously and it had a slower fsb. most users on the pentium 4 have used ddr ram which wasnt feeding the fsb. hell my p4 rig now has a 533 mhz fsb. im only getting 33mhz off the ram. but now we have dual channel addressing and all that good stufff so taht problems solved and rambus is all but a bad dream. I don't think the price is affected from anything but the fact taht it's new. ok im ranting and i want some tacos. later!
  • Reply 12 of 20
    banchobancho Posts: 1,517member
    Because the FSB is fixed at half the processor speed. That's IBM, not Apple.
  • Reply 13 of 20
    airslufairsluf Posts: 1,861member
  • Reply 14 of 20
    1337_5l4xx0r1337_5l4xx0r Posts: 1,558member
    Heh. Talk about overcompensating; a 2:1 bus ratio instead of 17:1 like in a dual 1.42 G4 (8.5:1 divided by two processors... ugh...).



    The bus isn't the issue. It's the ram. How can ram come close to saturating a 1.5Ghz bus? 256-bit data paths?



    Geez, I love typing that: 1.5Ghz bus.



    And wasn't it the 980 that is supposed to be dual core? I imagine they'll be made single core as well (for powerbooks and maybe imacs), but if they ARE dual core, expect ALL G5s to be dual (core), and on the high end, those yummy quad G5s we all fantasize about (dual core x 2) sometime in late 2004-early 2005.
  • Reply 15 of 20
    banchobancho Posts: 1,517member
    Isn't it nice to know that there is room to grow built in to these new chips? I see people worried how Apple will be able to keep the bus saturated but at least that piece of the puzzle is evolving independent of Apple. Everyone wants faster memory. As it's developed Apple should be positioned to take advantage of the increases almost immediately.



    This leads to a small question:



    Apple is shipping the low end tower with 333MHz DDR memory. Shouldn't you be able to pop that out and pack it with 400MHz DDR? I can't see why not. I also noticed that all the G5 machines ship with 2 sticks of memory. Does the new setup require memory installed in pairs?
  • Reply 16 of 20
    applenutapplenut Posts: 5,768member
    Quote:

    Originally posted by Bancho

    Isn't it nice to know that there is room to grow built in to these new chips? I see people worried how Apple will be able to keep the bus saturated but at least that piece of the puzzle is evolving independent of Apple. Everyone wants faster memory. As it's developed Apple should be positioned to take advantage of the increases almost immediately.



    This leads to a small question:



    Apple is shipping the low end tower with 333MHz DDR memory. Shouldn't you be able to pop that out and pack it with 400MHz DDR? I can't see why not. I also noticed that all the G5 machines ship with 2 sticks of memory. Does the new setup require memory installed in pairs?




    yes, memory must be installed in identical capacity pairs from the outside slots in.
  • Reply 17 of 20
    lixlix Posts: 56member
    You can use 333 or 400 in the low end, it will clock the 400 down to 333. It will not speed up the bus.



    Yes, you need to install in pairs as it is 'dual channel' DDR SDRAM
  • Reply 18 of 20
    banchobancho Posts: 1,517member
    The low end has an 800MHz FSB. What will keep the machine from making full use of faster RAM? I thought using slower RAM was a way of cutting cost on the low end.
  • Reply 19 of 20
    stoostoo Posts: 1,490member
    How about two 1.5GHz buses on the Dual 3GHz then?
  • Reply 20 of 20
    gizzmonicgizzmonic Posts: 511member
    Wasn't there an article about the Macs using the Nforce3 chipset once it's ready for production?



    I think the current chipset seems more hightech than what I've read about the Nforce 3. Do you think that the Nforce 3 will actually go into a Mac motherboard? And if so, will it be a low-end or high-end solution?
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