metalpython

Intel microarchitectures are only a maximum of 5% faster than AMD Zen

Discussion created by metalpython on Jun 20, 2018
Latest reply on Jun 22, 2018 by rwd4ever

Upon comparing Intel's Skylake (slightly old) but very optimised version (Skylake-SP which is used for LGA 3647 xeon processors) I found that in benchmarks from Cinebench to Geekbench the AMD Zen processor only suffered at most a 11% performance loss due to architectural design and I was even assuming that the AMD processor was running at max turbo boost (or very close to it) - If it hadn't been significantly less than max then there would have been almost no performance difference between the architectures.

For this i used the Intel Xeon Bronze 3106 and the AMD Ryzen Threadripper 1900x for comparison.

I used the Xeon Bronze because it has the same number of cores and very similar amounts of cache (if not a bit more which may have even given it more of an advantage) to the 1900X and no turbo boost (so comparison was easier). I used the AMD TR 1900X because the turbo boost was minimal (only 4.0GHz compared to base 3.8GHz clock speed).

The Bronze has a clock of 1.7GHz with nearly all other factors very similar or the same as the 1900X and so i used the clock as a comparison indicator.

Assuming the 1900X clock speed was at max turbo then 4.00 / 1.7 = 2.35 which means that the 1900X clock is 235% more than the Bronze one.

Lets compare the benchmark results (single core benchmarks to eliminate the hyperthreading differences (Bronze has no hyperthreading)):

- The increase from Bronze (B) to 1900X (X) for Cinebench R11.5 was 230%

- The increase from B to X for Cinebench R15 was 224%

- The increase from B to X for Geekbench 3 was 230%

235% (clock difference) - 224% (Lowest benchmark difference) = 11%

11 / 224 = 0.04910714285714 * 100 = 4.91% ≈ 5% increase in performance all down to the factors that weren't the same between the processors (mostly architecture e.g. Pipelining and perhaps other small factors).

These benchmarks were taken from www.cpu-monkey.com but all other sources showed a very similar trend.

So what do you think? Has AMD finally bridged the design and architectural gap between them and Intel while still keeping their processors cheap?

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