The CPU in the new tower

Posted:
in Future Apple Hardware edited January 2014
I know nothing about CPU design, but the new CPU we can't post pictures of has 12 capacitors on the die, as opposed to the 6 on the current G4. Can anybody tell me what that means? Twice as much voltage at the core? Multi-core? Additional integer units? Any guesses? Admins, if you feel your lock finger getting itchy, maybe you should nail this thread: <a href="http://forums.appleinsider.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=1&t=002245"; target="_blank">Masker's Silly Thread</a>

before you kill mine.



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Comments

  • Reply 1 of 26
    algolalgol Posts: 833member
    I don't know enough to help you on this one. But what is the name of this new CPU MPC7xxx is it the 7500 or what...?? In time.
  • Reply 2 of 26
    neutrino23neutrino23 Posts: 1,561member
    Probably means nothing to us. Most likely these are used to help reduce variations in the power supply voltage.
  • Reply 3 of 26
    eugeneeugene Posts: 8,254member
    HOLY SHIT, SUPER SECRET CPU DISCOVERED IN CURRENT EMACS ****CONFIRMED****



  • Reply 4 of 26
    LOL <img src="graemlins/lol.gif" border="0" alt="[Laughing]" /> <img src="graemlins/lol.gif" border="0" alt="[Laughing]" /> <img src="graemlins/lol.gif" border="0" alt="[Laughing]" />

    Ah Eugene you crack me up.....



    (I hope you didnt take to your new eMac with a sledgehammer to prove this..)
  • Reply 5 of 26
    wo damn double post sorry

    how do you edit these again

    (oh...BTW I took my bondi iMac apart a while ago and discovered to my total shock that it had a 5Ghz G5++ in it all along it had just been downclocked... but as soon as I saw this some guys in black suits burst in the room, grabbed the motherboard and left after hitting me over the head with an Office XP box and dropping it in their hurry to get out... I ran outside after them but they had already taken off in a titanium Gulfstream 5 with a TING5 -SJ callsign...When i opened the box the only thing in it was a 233Mhz G3 chip and a little hand written note, that said "dont tell ANYONE!" - SJ..... does anyone know what happened....)
  • Reply 6 of 26
    Eugene, you have to be more careful with that kind of information. Someone will see that photo and think there is a space where a second processor can be dropped in. And before you know it, there will be threads saying "eMac is dual-processor ready!" <img src="graemlins/lol.gif" border="0" alt="[Laughing]" />



    [ 08-02-2002: Message edited by: BrunoBruin ]</p>
  • Reply 7 of 26
    fawkesfawkes Posts: 80member
    Capacitors are used for power supply decoupling and are required for nearly all digital electronics, regardless of clock speed. For some BGA (Ball Grid Array) packages, the electrical paths between the die and the circuit board are inductive enough that capacitors are added to the package to make the decoupling more robust. If you look at the board, you will likely see many more capacitors sprinkled around the processor (underneath, more commonly, but not required) as well as around the other devices on the board.



    "Decoupling", by the way, is what we mean by keeping the power stable to the chip. In any power supply, there is parasitic inductance in the path from the main power supply and the die. This inductance impedes transient current demands of a chip (such as when a bunch of address or data lines all switch states at the same time). Capacitors provide local storage of charge to keep the chip running smoothly. Without them, the voltage would dip whenever there is an attempt by the chip to demand a fast change in current. (You'll often hear the term "ground bounce" thrown around, which is the effective 'raising' of the board ground during such current transients) Capacitors also provide a low impedance path to ground for high-frequency noise generated by the devices on the board. (Capacitors look like low-value resistors to high frequencies)



    Bottom line: more capacitors on the processor don't necessarily tell us much about the die inside.



    Hope this helps!
  • Reply 8 of 26
    thuh freakthuh freak Posts: 2,664member
    [quote]Originally posted by Fawkes:

    <strong>...blahbitty blah...technical woohoo...</strong><hr></blockquote>



    i think that was the most technical response i've ever seen in fh. it was very informative, and it didn't even mention a hint of flame. i am surprised. is fh changing? maybe my head isn't on right.
  • Reply 9 of 26
    big macbig mac Posts: 480member
    [quote]Originally posted by thuh Freak:

    <strong>



    i think that was the most technical response i've ever seen in fh. it was very informative, and it didn't even mention a hint of flame. [SNIP] </strong><hr></blockquote>



    I concur, that was a wonderful explanation there, Fawkes. The depth of your technical knowledge is quite impressive. Maybe you can tell us next when we're truly getting the G5.
  • Reply 10 of 26
    rickagrickag Posts: 1,626member
    You know, looking at that motherboard, it has a different shape than the infamous DDR motherboard, say the motherboard in my computer at work is different yet. Certainly the motherboard in the iMac is completely different.



    What's up with that, I thought Apple was going to a unified motherboard architecture. Have they lost focus with all these different architectures.
  • Reply 11 of 26
    programmerprogrammer Posts: 3,457member
    [quote]Originally posted by rickag:

    <strong>You know, looking at that motherboard, it has a different shape than the infamous DDR motherboard, say the motherboard in my computer at work is different yet. Certainly the motherboard in the iMac is completely different.



    What's up with that, I thought Apple was going to a unified motherboard architecture. Have they lost focus with all these different architectures.</strong><hr></blockquote>





    Not really -- different motherboards isn't nearly so important to avoid as different chipsets. It is the ASIC design & production that is difficult, and Apple is sharing much of those components across its line I believe.
  • Reply 12 of 26
    fawkesfawkes Posts: 80member
    [quote]Originally posted by Big Mac:

    <strong>

    [...]Maybe you can tell us next when we're truly getting the G5. </strong><hr></blockquote>



    Heh! Sorry, but the only thing that I can *confirm* is that I know Jack Squat about that!



    I am, however, a board designer and agree with Programmer. ASICs are very expensive to design and fabricate, but circuit boards are relatively cheap. In fact, after you draw the schematic for a design, you could have it laid out onto several boards of arbitrary shapes. I'm sure the G4 boards aren't exactly identical electrically, but, like Programmer said, the chipsets and basic design likely are.
  • Reply 13 of 26
    What the hell does the shape of the mobo have to do with the architecture?
  • Reply 14 of 26
    algolalgol Posts: 833member
    I was talking to a programmer I know and he says that the capacitors don't really have anything to do with the chip architecture but it could be an indication of a shift from .18u. to .13u. As in smaller pipe line requires more power to pump info through. Makes sense to me knowing the little I know about electricity. Anybody else out there that can back this up? In time.
  • Reply 15 of 26
    [quote]Originally posted by Algol:

    <strong>I was talking to a programmer I know and he says that the capacitors don't really have anything to do with the chip architecture but it could be an indication of a shift from .18u. to .13u. As in smaller pipe line requires more power to pump info through. Makes sense to me knowing the little I know about electricity. Anybody else out there that can back this up? In time.</strong><hr></blockquote>



    There's not a single reason to move to decaps (decoupling capacitors, bypass caps, etc.), but rather several that usually combine to justify that solution. Put in layman's terms, fast switching circuits demand so much current that they end up pulling the ground rail up and the power rail down. Decaps help with that. Moving to cheaper packages may end up providing more inductance in the package, meaning that the voltage coming out of the power supply is not necessarily the voltage that gets to the circuits.



    Now, anybody who knows about inductors and capacitors at this point is getting a little bit nervous because they have a tendancy to oscillate, but suffice it to say that smart people can work on the problem and lessen it.



    So, what does it mean that some chips (presumably newer ones) have more pacakage decaps than others? Probably that the transistors are manufactured comparitively more aggressively on the new ones than the old ones, related to the package cost. An optimist could say that it's a faster G4 or better, a pessimist could say that module costs are coming down a few bucks and that gets passed to someone's bottom line, not our wallets. Could also be that the chip in question is targetted to a lower voltage, so AC switching noise was a larger portion of VDD (longer battery life in whatever portable, or cooler running desktop).
  • Reply 16 of 26
    amorphamorph Posts: 7,112member
    [quote]Originally posted by Chrys Robyn:

    <strong>Could also be that the chip in question is targetted to a lower voltage, so AC switching noise was a larger portion of VDD (longer battery life in whatever portable, or cooler running desktop).</strong><hr></blockquote>



    If the eMac and the iMac are using the same G4 that the PowerBook is, then it's running at 1.3v as opposed to the 1.6v version in the G4s. That might explain the extra capacitors.
  • Reply 17 of 26
    eugeneeugene Posts: 8,254member
    There are no extra capacitors. Every 745x has those 12 capacitors, including the low-power versions found in PowerBooks and the regular versions found in the the Power Macs.



    On a side note, the 744x chips do have fewer capacitors...but no Mac has a 744x.
  • Reply 18 of 26
    algolalgol Posts: 833member
    thanks you thank you... So there has been no change to the # of capacitors. I figured this... Man we need some inside info for the forum where's Dorsal when you need him In time. <img src="graemlins/embarrassed.gif" border="0" alt="[Embarrassed]" /> :confused: :confused:
  • Reply 19 of 26
    I must have been thinking about an older G4. I wasn't aware the current ones had that many. Now the admins can lock this thread.



  • Reply 20 of 26
    rickagrickag Posts: 1,626member
    [quote]Originally posted by Programmer:



    Not really -- different motherboards isn't nearly so important to avoid as different chipsets. It is the ASIC design & production that is difficult, and Apple is sharing much of those components across its line I believe.<hr></blockquote>



    uh, I was trying to be funny. sorry if my attempt failed.
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