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Comment by angdis | Hacker News Reader

I suppose that "supercomputers" are all multi-processor these days, so the colossal FLOP numbers are counted as an aggregation over many processors and one has to coordinate these processors in any application that takes advantage of the FLOP specs.

Now I am curious what is the fastest single processor?

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I don't think knowing that is usefull. "Single processors" are all superscalar or pipelined these days, so the colossal single-thread FLOP numbers are counted as an aggregation over many arithmetic units and one has to coordinate these units (mainly avoiding branch mispredictions) in any application that takes advantage of them.

It's still relevant. Some applications remain single threaded due to data dependencies.

Mechanical CAD geometry kernels are one such application. Recently, I had a use case that demanded the peak single threaded performance.

In PC land, it's this chip clocked at 4.x Ghz: Intel® Core™ i7-4790K. It's multi-core performance is pretty great too, so it's not that big of a trade-off to maximize single thread performance.

I would be very interested in knowing what faster solutions exist. Are there any, regardless of instruction set?

On a per-core basis, probably Power 8: http://www.anandtech.com/show/9193/the-xeon-e78800-v3-review...

I guess it depends on how 'core' is defined. A single core of an Intel CPU can work on 2 threads at a time, the power 8 can work on 8.

I assume that when most people think of 'single core' performance, they really mean 'single thread'. I think Intel's CPUs win out there, based on your linked benchmarks.

If your memory bandwidth limited then, yes. Otherwise your better of with a decently clocked intel. Anything that spends a portion of its time running out of L2 or better on the Xeon will be significantly faster.

Looks like somebody got to ~8.7GHz through overclocking a ~4GHz cpu.

http://hwbot.org/submission/%202615355

I happened to catch an overclocking competition being streamed on Twitch one late night many months ago. It was really interesting to see more about the methods and techniques involved and how the competitions work.

See my comment above for exascale info. The single chip performance will vary wildly. The important measurement is how many operations of useful work per second per watt the system will do. That's the gist of it I've learned from HPC people.

Exascale is power-hungry so power must go way down and efficiency of calculation way up.

Probably an intel xeon (or i7?) overclocked and cooled with liquid nitrogen. There may be a specialized processor with higher performance, but I doubt it.

I use i7 2600k at 5.0 GHz for some time. Probably best option for ordinary human.

Interesting! I'm running this one: Intel® Core™ i7-4790K at 4.x Ghz (currently 4.2 for long term big problem stability)

What does your setup look like? Cooling, RAM, etc...?

And is it good for long term, like say crunch on it for a week type problems?

Water cooling from Antec, it fits into regular desktop case. Under load it makes sound like hoover. Some cheap RAM, some motherboard for $200, 500 Watt PSU. I use it for IDE (Scala compiler is slow).

No problem with stability, it ran a few times over weekend at full load. Maximal temperature about 90C. I have put quite high voltage. Over summer it goes down to 4.8GHz.

Nice! I'll need to pick up a new machine soon. Might give this a go to compare with my existing 4.3Ghz machine.

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