I suspect the improvements are even more dramatic going from Zen 1 through to Zen 5. AMD has really hit the jackpot with how scalable the Ryzen CPU is considering how they're able to improve the performance from year to year. This is a stark difference to the FX series during the 2010s, which saw very small YoY performance increases by comparison. Ryzen really is AMD's equivalent to what Nehalem/Core was for Intel back in the mid 2000s.
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.
>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.
>Instead of discrete, fully independent cores, AMD grouped processing units into "Modules"…
This argument has never made very much sense to me. Yes, the decision to group cores into modules with some shared resources did introduce a bottleneck and result in lower performance than having isolated cores. But this didn't make the processor worse than if it didn't have the additional cores at all. These processors were at their best on highly parallel workloads. AMD shipped far more cores than Intel at the same price. The contention for the shared front end was not serious enough to make up for the core count advantage. How is the module architecture an explanation for why the design failed, when the bottleneck only becomes relevant in situations where the design is winning?
It's hard to find benchmarks from 15 years ago. But Phoronix finds what I describe: the design doesn't scale quite as well as a "true" eight-core design, but still scales better than the competition of the time which had lower core counts. Though it does seem straightforwardly bad at some workloads.
It's as FlowingRiver said. If we were to release the same parts again with modern software, Bulldozer would be a far stronger competitor to Sandy Bridge. FX aged better than Intel's designs of the same era. But Intel's designs were better to start with, so I'd still take the Core.
The reason they sucked is that they ran hot and their per-core performance was terrible.
Yokolos · · focus · HN ↗
FlowingRiver · · focus · HN ↗
PorciiVorbesc · · focus · HN ↗
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:
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.c4rnifex · · focus · HN ↗
This argument has never made very much sense to me. Yes, the decision to group cores into modules with some shared resources did introduce a bottleneck and result in lower performance than having isolated cores. But this didn't make the processor worse than if it didn't have the additional cores at all. These processors were at their best on highly parallel workloads. AMD shipped far more cores than Intel at the same price. The contention for the shared front end was not serious enough to make up for the core count advantage. How is the module architecture an explanation for why the design failed, when the bottleneck only becomes relevant in situations where the design is winning?
It's hard to find benchmarks from 15 years ago. But Phoronix finds what I describe: the design doesn't scale quite as well as a "true" eight-core design, but still scales better than the competition of the time which had lower core counts. Though it does seem straightforwardly bad at some workloads.
<a href="https://www.phoronix.com/review/amd_bulldozer_scaling/7" rel="nofollow">https://www.phoronix.com/review/amd_bulldozer_scaling/7
It's as FlowingRiver said. If we were to release the same parts again with modern software, Bulldozer would be a far stronger competitor to Sandy Bridge. FX aged better than Intel's designs of the same era. But Intel's designs were better to start with, so I'd still take the Core.
The reason they sucked is that they ran hot and their per-core performance was terrible.