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FlowingRivertoday at 9:10 PM1 replyview on HN

That is all true but I will defend the FX series a little. Mostly now that there is a lot of software that scales across cores better now, they haven't aged as terribly as others have. They aren't great but not terrible considering.


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PorciiVorbesctoday at 9:28 PM

>Mostly now that there is a lot of software that scales across cores better now

That's pretty much irrelevant since the AMD's FX arch's issues weren't that SW at the time wasn't using all the 8 cores. Intel dropped the Core 2 Duo and Quad into the era where most SW was still stuck in single threaded for a long time and those CPUs still ripped single-threaded SW tasks regardless.

Here's the big reasons why the FX sucked back then and why they still suck today in the multi-thread SW era:

  Instead of discrete, fully independent cores, AMD grouped processing units into "Modules" where each module contained two integer execution units, but they had to share critical resources like one FPU, the instruction fetch/decode pipeline, and the L2 cache so when both "cores" inside a module were heavily taxed especially with math or physics-heavy calculations (like in videogames), they choked fighting over shared hardware.

  AMD designed Bulldozer with a very long pipeline, betting they could sacrifice efficiency per clock cycle in exchange for extraordinarily high clock speeds(a-la Intel Pentium 4) but the IPC was so bad that an FX core was often slower clock-for-clock than AMD’s previous-generation Phenom II chips and also their power consumption exploded. 

  FX processors were plagued by high cache latencies and an inefficient memory subsystem as another bottleneck.

So unless you're into collecting vintage CPUs as display pieces, this one definitely belongs in the e-waste pile instead of burning electricity, because it did not age like wine with the adoption of SW multi threading like people were hoping.
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