"Crippled" DDR on new G5's?

Discussion in 'Macintosh Computers' started by erockerboy, Aug 14, 2003.

  1. macrumors member

    Jul 25, 2002
    SEA, WA, US
    I recently saw the following info posted on Unicornation.com - anyone care to comment? Please understand that I'm in a position of ignorance here, so don't shoot the messenger... the punchline seems to be that for us DAW users, it would be worthwhile to wait for the next rev of the G5's before jumping in.


  2. macrumors 6502a

    Mar 20, 2003
    Faster memory is always coming out; it's a fact of life, just like faster processors come out as well.
  3. macrumors 68020


    Jan 1, 2002
    Pittsburgh, PA

    complain complain complain.

    go do something constructive. :D
  4. macrumors 65816


    Nov 24, 2002
    Tampa, FL
    exactly! Shut up already.

    Article was probably written by a closet PC user who is pissed that they still use windows.
  5. macrumors demi-god


    May 14, 2002
    Well, this part is completely false:

    and this part:

    is referring to Rambus which will hardly be a widely used replacement for Dual-Channel DDR (IMHO). It certainly won't be an inexpensive option.

    Based on the application tests shown at WWDC, I think the performance of these systems will be more than enough for just about anyone's needs.
  6. Moderator emeritus

    Jun 25, 2002
    Gone but not forgotten.
    First of all, are 1.0 releases ever completely safe?

    How many cars, computers, etc. work without a glitch first time out?

    As far as I know, the G5 machines are not perfect but they're impressive. Are they going to reach their full potential right away? No! They're being released with an operating system working in a hybrid 32-64-bit mode.

    As far as DDR RAM goes, saying that there's a new standard and populating motherboards with actual specimens are two different things. It was surprising to me that Apple chose RAM that was already available instead of helping develop some innovative packaging which contained much faster memory. Then again, in the initial PowerMacs, they used 72 pin SIMMs in pairs. With the PCI PowerMacs, they used DIMMs, ahead of the rest of the industry.

    Newer machines will be faster and better--that's the way of things. :)
  7. macrumors 604


    Aug 9, 2002
    Springfield, OR (Home of the Simpsons)
    The only thing faster then DDR400 will be DDR-II which will not be a standard for probably another year. It might make it into high end machines come the first of the year but it is still very pricey.
  8. macrumors 6502a


    Nov 29, 2002
    That article is probably written by same person who complained about unfairness of early test comparison between G5 and Pentium PC's.
  9. macrumors 68040

    Powerbook G5

    Jun 23, 2003
    St Augustine, FL
    I am confused because if you take just about any high end performance PC, they use DDR 400 RAM, too...so if they accuse Apple of using "out of date" tech, then accuse Dell and Gateway and Toshiba and Sony and etc, too...we just got a brand new top of the line Dell system for the family computer and guess what? It uses DDR 400 RAM, too...I don't see them bashing Dell for using DDR 400.
  10. macrumors 604


    Aug 9, 2002
    Springfield, OR (Home of the Simpsons)
    I bet it doesn't used paired DDR 400. Meaning it still runs at half the speed of the memory architecture of that in the G5.
  11. TEG
    macrumors 604


    Jan 21, 2002
    Langley, Washington
    Rambus will never become a major player (Heck Intel doesn't even make boards that accept RIMMS anymore, and were the only ones who ever did (In great Quanity)), because they have quirks, act like simms and cost as much as the "Star Wars" Defense Project.

    I would like to See DDR-II, but we all know that it may be a while before we'll have them.

    With sentiments like that guy's, I know now why the Cube failed.

  12. macrumors regular

    Jul 12, 2003
    The most inaccurate part is this:

    "Also, a point no one seems to has mentioned. Altivec has been updated, meaning all apps that took advantage of the Altivec processor need to be updated (re-coded) to take advantage of the G5s speed."

    I suggest that no-one has mentioned it because it is completely false. The Altivec unit is slightly different, but use the same instructions, I believe.

    Apps have to be re-compiled for the G5 to see the biggest speed gains, but that is true of most new processor designs- and I don't think this is because of Altivec being a slightly different in the G5 (more like the older G4's, I believe). It won't be like the jump to PowerPC, where many apps were much slower on a 6100 than they were on a Quadra 840 or 950.
  13. macrumors G5

    Sun Baked

    May 19, 2002
    When the computer was announced, people looked around and found that there really were not that many large sticks of memory to be had.

    It even seemed that Apple was offering memory configurations that the market couldn't supply, yet.

    It's a little hard to say that Apple is using a dead standard, when it's hard to buy 1-2 GB sticks of memory for the darn machines at DDR400.

    Like, how would you expect to add DDR2 memory to the machine if Apple offered it?

    With a home mortgage?
  14. macrumors 68030


    Dec 7, 2002
    Florida, USA
    Actually, some Altivec commands are extremely slow (slower than it would be without the Altivec) and others don't work at all. So yes, some apps do need to be recompiled due to the change.
  15. iPC
    macrumors 6502


    Jul 22, 2003
    East Windsor, CT
    Not that big of a shift, true. But still... why do you think Adobe was there for the intro? The get to sell new "G5 optimized" stuff, offer minor bug fixes and new feature or two, and watch the faithful upgrade their 1 yr old software! :mad:


    What can you do?
  16. macrumors 68000

    Daveman Deluxe

    Jun 17, 2003
    Corvallis, Oregon
    The PPC970's vector pipelines include all 162 instructions in the AltiVec specification. That said, the vector processor is poorly integrated into the unit. It seems that it was really just sort of shoehorned in there (remember, there is no vector processor in the Power4). As a result, the current version of the 970 is not any better than the G4e at vector processing, and it is even worse at some instructions.
  17. macrumors 68040


    Jan 15, 2003
    51st State of America
    Not make a purchase?
  18. macrumors 65816

    Mar 31, 2002
    Maryland, USA
    Oh come on, we have the fastest bus on the planet now. 1 Ghz! Dual independent buses at that meaning data doesn't get crammed waiting to go in while other data goes out! Apple developer specs say with 2 GB PC-3200 modules (about $1100 through Pricewatch.com) you can get 16 GB of RAM into the machines. The system runs so much cooler because of the great design of the locations of the fans. Cooler means faster. To top it off, no longer are we limited to ATA/133 ATA, we have Serial ATA at 1.5 GB a second on the hard disk. The biggest slowdown on any machine is the hard disk, not the chips. The 1.6 Ghz G5, nice entry level machine, but not the one I'd get. I'd either get the 1.8 Ghz or the 2 Ghz. The 1.6 doesn't even have PCI-X. This coming off Macs that had buses at a maximum of 167 Mhz while all the people on this board were whaling that the bus made a huge difference. You got your faster bus, you got your faster hard drive, you got your memory capacity, you got your faster PCI slots, you got your faster AGP slot. You even got your digital audio ports. The way people carry on in here, they are expecting the M-5 from Star Trek to actually have been made 30 years ago and available in the desktop today. PCers are just jealous. We have the most secure system on the planet, and now the fastest for under $3000 with built-in developer tools. The tests were run at 32 bit. Imagine what it will be like at 64 bit. Oh and did you notice, the Opteron has to be rebooted to switch from 64 bit to 32 bit applications. The G5 does not. Imagine the time savings there!
  19. macrumors 68040

    Powerbook G5

    Jun 23, 2003
    St Augustine, FL
    I personally cannot wait for the G5s to make it into maturity across Apple's different product lines.
  20. macrumors 65816

    Aug 20, 2001
    Yeah whoever wrote that article is out of touch. But anyway, since everyone already knew that...


    Dual channel DDR isn't unusual in PC land, and in fact dual Opterons can support 4 channels of DDR (although current dual Opteron boards only have 2 channels). Tyan has such a board coming, but all those DIMM slots (16) make it huge and, I bet, expensive.


    Rambus lost their first battle for the desktop, but the war isn't over yet.


    I think they all work, just some memory commands require that the pipeline be flushed, as far as I know.


    A processor at a given clockspeed is exactly the same "fast-ness" at every temperature that it can run at without error.

    No, it does not. At this link you can see AMD making repeated claims about "simultaneous 32- and 64-bit computing".

  21. macrumors regular

    Mar 25, 2003
    Bridgewater NJ
    Most of the article is crap but he does have a point about the memory, the G5's 1 GHz bus (8 GB/s peak) is going to be "bottlenecked" by Dual Channel DDR-400 (6.4 GB/s peak). Not that it matters much as the G5 is fast enough already. It's just that it (the G5) will become significantly faster when Apple implements PC4000 DDR-500 (which is out by the way) or Quad Channel RDRAM. Remember, more speed is always a good thing. :)
  22. macrumors 68040

    Powerbook G5

    Jun 23, 2003
    St Augustine, FL
    This is still a brand new system...give it time to mature and we'll all be amazed with the capabilities, I am sure.
  23. macrumors regular

    Jul 12, 2003
    How does a processor without an altivec execute an altivec instruction?

    I've never heard anything to that end: link?

    Lots of the "970 is crap at altivec" comments are from people who have heard comments from people who read the first two Ars Technica 970 articles. There were mistakes in their discription of the unit, which are corrected here:

    But the original article was just criticising how the unit managed dispatches- not that it couldn't handle some of the altivec instruction set. If it wasn't compatible with the existing instructions from the G4, then it would be pretty useless to Apple. The 970 was designed by Apple and IBM together. I think Altivec compatibility was a major target for them.

    The recompiles are for optimisation for the new (to the Mac) architecture of the rest of the chip that evolved from the POWER4- not for the only part of the 970 which came from the Mac's existing processors.
  24. macrumors regular


    Jul 2, 2003
    Chicago, IL
    Not sure that this is a pertinent, but... I sometimes use my parents' Pentium4 which is 1.4 ghz. It has the aforementioned rambus memory, and is ridiculously slow. I had to order the RIMM from the internet b/c nobody in town sells it. It is complete garbage. Thankfully, I have my 400 mhz imac right next to it on the same desk. I am so much more productive thanks to Apple and OSX. I can't wait till my G5 ships so I can see just how pitiful the pentium really is.
  25. macrumors newbie

    Jun 15, 2002
    Middleton, WI
    Don't believe everything you hear.

    A lot of what you just said is completely false.
    Rambus sucks, altivec hasn't changed in the G5 (it's only gotten more room to work with it now), etc etc

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