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A comment on Why Apple ditched PowerPC, and what it says about Apple ditching Intel. Parent comment

Re:Why Apple ditched PowerPC, and what it says about Apple d... by a1369209993 on Saturday June 20, 2020 @04:22PM (#23586950)
Sure, but that's them having a competent (well, less incompetent) ISA and microarchitecture; that they've made better use of the transistors available, not that they've achieved better feature density than what would be expected from where they are on the Moores law curve.

Also Intel and AMD have not delivered higher performance via more cores; they delivered lower price for (say) 64 cores worth of performance, by putting them all on the same chunk of silicon (edit: or at least in the same package). (There are some slight improvements in inter-processor interrupt and cache-forwarding latency, but if that's a performance bottleneck, the problem is bad parallelization at the code level.)

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Re:Why Apple ditched PowerPC, and what it says about Apple d... by wolfgke on Sunday June 21, 2020 @09:07AM (#23591803)
> Sure, but that's them having a competent (well, less incompetent) ISA

Have you looked at the encoding of Thumb-2 (T32) and particularly A64 (their newly designed instruction set for 64 bit)? Their instruction encoding is in my opinion much more convoluted than x86.

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Re:Why Apple ditched PowerPC, and what it says about Apple d... by DuskStar on Saturday June 20, 2020 @05:43PM (#23587583)
> they delivered lower price for (say) 64 cores worth of performance, by putting them all on the same chunk of silicon.

Arguably AMD did the exact opposite - lower prices via splitting a processor into multiple pieces of silicon. (Chip price scale exponentially with area at the high end)

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Re:Why Apple ditched PowerPC, and what it says about Apple d... by a1369209993 on Saturday June 20, 2020 @06:24PM (#23587916)
Well, my point there was that a 64-core CPU is not (significantly) higher performance than 64 single-core CPUs, so multi-core is - if a improvement at all - a price improvement, not a performance improvement, but fair point about the price-vs-area scaling.
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Re:Why Apple ditched PowerPC, and what it says about Apple d... by ido on Sunday June 21, 2020 @01:28AM (#23590063) 

    Sure, but that's them having a competent 
    (well, less incompetent) ISA and microarchitecture
Hasn't x86 been basically RISC-like internally since the pentium-pro/amd k6? Is the translation layer that big of a hindrance?
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Re:Why Apple ditched PowerPC, and what it says about Apple d... by blattimwind on Sunday June 21, 2020 @09:49AM (#23592002)
ISA doesn't matter nearly as much as people think, unless it's something really different (like VLIW/EPIC/...).
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