Why Intel was a bad idea (And should have gone AMD)

Discussion in 'Mac Pro' started by crainial, Mar 15, 2006.

  1. crainial macrumors newbie

    Jun 16, 2003
    the following is some good proof of why AMD should have been the processor in the Mac, not intel. It comes from Sharikou who has some good hard facts on this stuff (link to follow)


    AMD64 is five generations ahead of INTEL

    It's impossible for me to cover this topic in great detail, so I will hit the key points only.

    AMD64 Instruction set

    In Feburary 2003, on the eve of AMD's launch of the AMD64 family CPUs, INTEL expressed its disblief. According to Richard Wirt, an INTEL senior fellow, four separate design teams at Intel had examined how the company could take one of its 32-bit chips and transform it into a 64-bit machine, all four Intel teams concluded that such a feat was not doable.

    INTEL did try hard to do 64 bit on x86, but their engineering didn't know how.

    But the grand masters at AMD did what INTEL thought was impossible. Opteron 64 hit the market in April 2003 and quickly won almost all performance benchmarks.

    Seeing is believing, INTEL tried to reverse engineer AMD's instruction set onto Pentium IV and Pentium 4 based Xeon. Emulating AMD64 instruction set was easier on Pentium IV, because it had a 36 bit physical address. However, benchmarks show INTEL's EM64T runs slower under 64 bit mode than 32 bit mode. Moreover, INTEL used some old AMD PDF files, and did a bad job, some Microsoft and Linux code developed on AMD64 failed on run on INTEL's clone. As of today, INTEL's EM64T is still missing some crucial capabilities of AMD64.

    But running AMD64 instructions on Pentium III proves to be much harder, as of today, INTEL hasn't yet figured out how to do 64 bit on Pentium M and Core Duo.

    And AMD is not sitting idle, it's adding a new set of instructions to the AMD64. INTEL engineers will have more sleepless nights digesting AMD PDFs.

    True Multi-core

    AMD64 architecture was designed to be true multi-core from the ground up. A multi-core CPU is much like a multi processor system, the cores must communicate with each other to maintain consistency. Inside the AMD64 CPU, there is a crossbar switch that connects the multiple cores together, so they communicate internally and at extremely high speed. We see from benchmarks that dual core Opteron is almost twice as fast as a single core Opteron at the same clock speed.

    In comparison, INTEL's dual core implementation is a kludge. In INTEL's design, the two cores share the same FSB, when they need to communicate, they first go out to FSB and come back again, without knowing they are sitting next to each other. The result? Poor performance .

    This AnandTech article provides good explanation of the dual core designs.

    The Embedded Memory Controller

    Chip design gurus have long realized that a major bottleneck in system performance is memory latency. Just like memory is much faster than hard disk, the CPU is much faster than memory. When a CPU needs to access memory for instructions or data, it has to wait for the memory content to be retrieved, the time of waiting is the latency. During the waiting period, the CPU can't do anything.

    In the old FSB based architecture (all INTEL's), the memory controller is in an external chip called the north bridge, while the CPUs run at 2-3GHZ, the conventional memory controller runs at about 200MHZ. Furthermore, in the old FSB design, the data have to make two hops, from memory to memory controller, then to the CPU. As we can see from this article, memory latency in a Pentium 4 design is between 300 to 400 clock cycles.

    In AMD64 design, the memory controller is embedded in the CPU and runs at CPU frequency, the CPU connects directly to the memory without any intermediate. As we can see from this IBM test on single and dual core Opteron, memory latency on the Opteron is only about 50 nano second for local memory access.

    Like the Opteron, all modern CPUs, such as Alpha EV7, IBM Power5, SUN UltraSparc T1, AMD Geode LX, Athlon 64, Sempron 64, Turion 64, have embedded memory controller(s).

    From INTEL roadmap as far as 2009, we don't see an embedded memory controller design.

    Cache Coherent HyperTransport (ccHT)

    In a N processor AMD system, since each CPU has its own memory controller and associated banks of memory, there are N memory controllers which provide N times the memory bandwith. To have these N memory controllers act coherently, there are multiple ccHT links between AMD CPUs, which is used for fetching memory from another CPU. As we can see from the IBM document referenced above, in the case of remote memory access, the latency is also quite small.

    INTEL is rumored to work on something similar to ccHT called CSI, however, since the cancelation of the Whitefield project, CSI is missing from INTEL's foreseeable roadmap.

    Direct Connect Architecture

    In FSB based architecture such as INTEL's, the CPU, Memory and I/O share the bandwith of a uni-directional bus, just like many folks share one phone line in a conference call --- only one guy can talk in either direction. In AMD64 architecture (Opteron, Athlon 64, Turion 64, Sempron), there are separate dedicated connections between CPU and Memory, between CPU and I/O, between CPU and CPU, between CPU core and CPU core. In AMD64, there is no crosstalk, and everything is bi-directional--traffic goes both ways the same time.

    From INTEL's roadmap, it's stuck with FSB architecture until at least 2009.


    INTEL is 5 generations behind AMD, and there are other major areas that INTEL is lacking, such as IOMMU for fast DMA. To match AMD in 2 core performance, INTEL will have to use very large cache size, which will negate its shrink to 65nm. At 4 core and up level, INTEL is simply hopless.

    posted by Sharikou, Ph. D @ 11:09 PM
  2. calebjohnston macrumors 68000


    Jan 24, 2006
    I fell asleep after the first sentence.

    Mmm, if only your opinion mattered to the company -- or anyone for that matter.
  3. DakotaGuy macrumors 68040


    Jan 14, 2002
    South Dakota, USA
    Going with Intel instead of AMD had more to do with the business side of things then the technology behind it. Now since all Mac users have became strong advocates for Intel, I don't think you are going to find many AMD fans around here anymore. Intel is a far superior company with a lot more money and muscle then AMD. Apple made the right choice. AMD is yesterdays news. I would be suprised if they survive in this "Intel World" much longer.
  4. plinden macrumors 68040


    Apr 8, 2004
  5. Oryan macrumors 6502a


    Apr 1, 2005
    Lincoln, NE
    Yes, I think Apple made a good choice in going with Intel based on their processor roadmap. Although I must speak up as an AMD fan. Intel's monopolistic business practices worry me. I'm really hoping AMD wins their lawsuit against Intel. :)
  6. virus1 macrumors 65816


    Jun 24, 2004
    wow.. you'r attention span is really small...



    where was i? oh ya.. i made it to the third sentence.
  7. steelfist macrumors 6502a

    Aug 10, 2005
    i read the whole thing. :)

    it has some good points. however, IMO, Intel is better in the long run.
  8. themacman macrumors 6502

    Jun 7, 2004
    AMD might be better according to this but apple chose intel there must have been a reason why.
  9. After G macrumors 68000

    After G

    Aug 27, 2003
    Why AMD is behind (or why Apple chose Intel).

    AMD may be more behind than you think.

    AMD's integrated memory controller means memory updates are tied to processor updates. AMD is only now getting DDR2 RAM. (This year).

    AMD processors are all 90 nm. Intel is set to transition to 45 nm process, and currently sells 65 nm processors.

    AMD makes worse mobile processors. In real world use, 1/2 hour less of battery life.

    AMD Live isn't as focused as Intel's Viiv. It seems like a copycat me too thing with regards to media center functionality.

    AMD has less resources if they mess things up. Even though they've been doing well, they can still screw the pooch if they trip up.

    AMD has only two fabrication facilities that I know of. And we all know that Apple has enough supply issues as it is.
  10. portent macrumors 6502a

    Feb 17, 2004
    AMD's got fast desktop chips. (So does IBM.)

    Intel's got fast mobile chips.
    Intel's got compilers and engineering support that allow Apple to rapidly optimize its software for a new platform.
    Intel's got entire chipset and mobo designs.
    Intel's the only company, other than Apple, that creates legacy-free system acrhitectures.
  11. topicolo macrumors 68000


    Jun 4, 2002
    Ottawa, ON
    Don't forget that Intel has more than enough manufacturing capacity to handle any kind of demand Apple might place on them
  12. MacTruck macrumors 65816


    Jan 27, 2005
    One Endless Loop
    Don't expect Mac heads to agree with anything other than what Steve says. Article makes perfect sense but in reality when opening a video or word processor you won't notice any difference. All that technical babble amounts to about a half a second faster doing anything. Who cares. ALL the chipmakers suck.
  13. hookahco macrumors regular

    Jun 11, 2005
    To Live n Die in L.A. California
    wow you guys must be avid readers.. I saw the heading "True Multi-Core" and saw what was under (and above it) and i just scrolled down to read the comments..
  14. DCapple macrumors regular


    Feb 28, 2006
    i agree!! having intel on mac is a marketing strategy..i have to say still if ill be given a choice i will choose AMD! :cool:
  15. Shamus macrumors 6502a


    Feb 26, 2006
    I am sure Apple did their research before changing chip architecture.
  16. Dont Hurt Me macrumors 603

    Dont Hurt Me

    Dec 21, 2002
    Yahooville S.C.
    The biggest reason Apple didnt go AMD is because Intel is GIVING AWAY free Integrated Graphics!!! Buy 1 Cpu and get free graphics! sure they are at the very very bottom of any chart but apple doesnt care. We will just spin and lie, its worked for the president for 5 yrs, should work for us. Heck we may even charge a xtra 100 bucks.
  17. Max on Macs macrumors 6502

    Max on Macs

    Feb 25, 2006
    Milton Keynes, UK
    I personally believe that Apple made the right choice with AMD. And not because of anything Steve Jobs said either, I can make my own conclusions about two x86 processor manufacturers.

    Firstly, Intel has a good roadmap of what they are going to do in the next few years. AMD says things but don't have a proper roadmap like Intel's.

    Secondly, Inte's Core chips perform very well and use less power then AMD's mobile chips. Intel's upcoming desktop chips also perform significantly better than anything AMD is talking about.

    Given all that Intel looks like the best choice. Then there's the Switch campaign. People associate Intel with PCs, so if Apple can get people to associate Intel with Macs too, they shouldn't be too scared to make the switch.

    Just my opinion.
  18. andiwm2003 macrumors 601


    Mar 29, 2004
    Boston, MA
    gee, i still can't understand that everlasting AMD vs. Intel debate.

    Can somebody tell me what the performance difference between an AMD vs. Intel system running Photoshop or iMovie or iPhoto is? 10%? 12%?

    Who cares about 10%?
    Yes there may be 2% pro users who would notice the 10% for rendering a 20hrs job. But for them it's the far better solution to buy a second mac.

    It's better to sacrifice 10% performance and go with the more reliable vendor with the more predictable product pipeline. For the moment that is Intel.
  19. crainial thread starter macrumors newbie

    Jun 16, 2003
    not so. besides the fact that the test was a pre-production chip that no one else has tested, ie Tom's Hardware or other third party, the Athlon 64 FX-60 is a currently shipping chip. If you look closley, AnAnd used a crippled AMD box with an out of date BIOS. All the Intel procs are updated Pentium 3's. When conroe ships, then test it against a currently shipping Athlon. Also for the pro end, the Core procs are not 64-bit, and probably won't for AT LEAST a year, and only after they copy AMD64 instructions. Conroe/Merom, guess what, it is 32 bit as well. Too bad OS X is a 64-bit OS with lots of wasted potential.
  20. iGary Guest


    May 26, 2004
    Randy's House

    :rolleyes: :rolleyes: :rolleyes: :rolleyes:
  21. Dont Hurt Me macrumors 603

    Dont Hurt Me

    Dec 21, 2002
    Yahooville S.C.
    Come on those free gpus had to be attractive to Apple. I would like to see some proof of what those things cost Apple if anything? 99 cents? Free;) Anyways Apple has based their hardware on roadmaps before, remember Motorola and IBM. Motorola was famous for so called roadmaps.
  22. andiwm2003 macrumors 601


    Mar 29, 2004
    Boston, MA
    actually Barefeats.com shows that the IntelMac mini with integrated graphics does pretty good in all relevant applications. so the integrated graphics can't be that bad after all.
  23. Dont Hurt Me macrumors 603

    Dont Hurt Me

    Dec 21, 2002
    Yahooville S.C.
    Its not bad if you are comparing it to what? its a last place GPU unless you compare it to Intels older Integrated graphics. Thats the facts. You cant go much lower on Gpu's then this. I have said it before apple is going to use graphics to seperate the models since all are going to have cpu's sitting in sockets.
  24. Dane D. macrumors 6502a

    Apr 16, 2004
    I did read the whole thread, but I think people are forgeting that the CPU is just one part of the whole hardware system. Sure the OP brings facts to the table but what about the motherboard, the RAM, the Vcard, the HD and all the other components? I like the decision to use Intel, besides this is first generation Mac-Intel stuff. It can only get better, especially if Apple is working with Intel closely on THEIR hardware needs. From what I have read and heard from PC users, AMD is better at gaming than Intel but who cares. I don't make money playing games, I make money with pro apps like Quark, Photoshop, Illustrator. So if Intel can produce quality chips and supply them then all the more power to them.
  25. Hunts121 macrumors regular


    Mar 21, 2005
    what are you talking about? Conroe and Merom are 64 bit, this has been known for a while, hence why many people are waiting for those chips.....



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