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Comment by alasdair_ | Hacker News Reader

I have an 8700K that has been running at a stable 5GHz for several years with just a basic watercooled setup and manual tweaking.

Will the 12900K give a meaningful performance bump at the same clock speed?

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About 52% single-threaded, 196% multi-threaded improvement.

https://www.cpubenchmark.net/compare/Intel-i7-8700K-vs-Intel...

And probably also better performance per watt should you care about that.

Not sure about that one; TDP isn't exactly the same as actual power consumption, but for i9-12900K it is more than doubled.

You're comparing the 8700K TDP to the 12900K maximum turbo power (which you can only "achieve" when using all cores fully). In "normal" usage 12th gen is very energy efficient and perform (unsurprisingly) much better than AMD Zen 2/3 SKUs.

You appear to be correct. I dug around a bit, and on Intel's ARK there are 2 numbers: Processor Base Power (125W) and Maximum Turbo Power (241W, same as the one used with the benchmarks). It appears the Processor Base Power might be a closer equivalent to TDP than the other one. If that's the case, the 12900K is much more efficient than the 8700K.

Can't edit the comment anymore, but I made a mistake. The Maximum Turbo Power explanation is as follows: "The maximum sustained (>1s) power dissipation of the processor as limited by current and/or temperature controls."

Somehow I have misread it to mean that it can peak up to said power limit for UNDER 1 second, which is incorrect - the CPU will run at that limit for as long as cooling allows. The CPU will gulp down ~240W when under full load, as evidenced here at ~24 minutes: https://www.youtube.com/watch?v=fhI9tLOg-6I

“Normal” usage isn’t going to be terribly more energy efficient - efficiency doesn’t change much depending on number of cores loaded. (Unless you’re only loading efficiency cores in the case of 12th-gen Intel.) (More cores might actually be more efficient if it thermally limits the CPU - in that case the frequency will be throttled, which will put you at a more efficient place on the voltage curve.)

Tom’s Hardware 5800X3D review[1] has some efficiency numbers if you scroll down. High-end Zen 3 chips seem mostly a bit more efficient than high-end 12th-gen Intel. By far the most efficient CPU tested is the 5700X, which is AMD’s fastest 65W TDP part. They don’t have any low-power Intel chips (e.g. Core i7-12700T) in the test. (Though I’ve always found retail availability of low-power Intel chips to be terrible.)

1. https://www.tomshardware.com/news/amd-ryzen-7-5800x3d-review

If you are referring to the all-core Handbrake efficiency graph then I'm not sure what's to complain about. The 12th-gen top-end SKUs perform far better while being roughly as efficient as the slower AMD parts, which is a clear win in my book. The 5700X performing well here is not surprising, as it's heavily restricted by the low TDP so in this all-core workload it might even remain under 4 GHz, also resulting in the lowest performance by far.

The situation is very different for lightly threaded loads (e.g. what PCs tend to do a lot of the time, this also includes most games).

I watched GamersNexus' 5800X3D review a few days ago, and the thing that stood out to me was their direct measurement of power draw on the 12V rail; it included a 120W result for the 5950X, and 240W (!) for the 12900KS. These parts are pretty comparable for the workloads I care about (compilation, mostly) but Intel's best part does the same job in roughly the same amount of time, for more money and twice the power draw. Is there something I'm missing, before I just buy the AMD for an upgrade?

For Handbrake the 12700K performs about 12% faster than the 5900X while being about 13% less efficient - I don’t think “perform far better while being roughly as efficient” is a fair characterization there - it performs better by about the same amount as it’s less efficient.

And the 5700X having low performance is taken into account by efficiency metrics - efficiency is performance divided by power draw, so whatever it in performance it more than gains in reduced power draw. (Of course, you might value your time more than your electric bill.)

Thank you.

That link assumes the 8700K is running at 3.7GHz - any idea if there is still that much improvement given that mine is running at 5GHz?

The stock 8700k boosts upto 4.7 Ghz. I don't think your extra 300Mhz will make that much of a difference.

TBH, there are people way more qualified in this area than I, but AFAIK Intel CPUs run at the turbo speed as long as they have sufficient cooling, and the benchmarks run at maximum performance available, which would be 4.7GHz in this case. Therefore, the benchmarks should be pretty close to your OC. You could verify this theory by running the benchmark yourself.

Good to know - thank you!

Edit: I did and you are right. I’m about 10% higher than the benchmark but still WAY below the i9-12900KS (by 25% single threaded)

Time to upgrade :)

I had an i5 9600k that ran 5ghz all cores, and swapped to the i7 12700k. The i7 is still a lot faster out of the box and I undervolted it a bit while running at 5.1 ghz so it's also very quiet.

I benchmarked it. I get a score of 3068 for single-threaded performance, which is around 10% faster than the stock 8700K stats but it’s still 25% below the i-9 12900KS.

I guess it’s time to upgrade :)

In essence you get a CPU that is 4 (!) architectures newer.

Here are the architectures of Intel (according to Wikipedia):

1. i686 (Pentium Pro, Pentium II, Pentium III)

2. Core (Core 2)

3. Nehalem (Core i7-920, Core i5-750)

4. Sandy Bridge (Core i 2000 series)

5. Haswell (Core i 4000 series)

6. Skylake (Core i 6000 series)

7. canceled due to low yield

8. Sunny Cove (Ice Lake mobile 10xx and desktop 11xxx)

9. Willow Cove (Tiger Lake mobile 11xx)

10. Golden Cove (12xxx and 12xx)

Did you purposefully leave out Broadwell, or was it a mistake? (If it wasn’t a mistake, I’d be interested to hear you expand on why, I know it was a bit of a weird release.)

I think broadwell was a process shift, not a microarchitecture shift.

They also left out the whole Netburst (and it's decedents) arch too.

I think Intel would rather we all forget about netburst.

Netburst is not based on P6 (i686). Core is a development stemming directly from Enhanced Pentium M which stems from Pentium III. All others build on this. Broadwell is Haswell on a new node (14nm instead of 22nm).

If you are asking a general question about single threaded performance, then YES. Modern CPU performance is about so much more than clock speeds, and the TLDR is that there are many non-orthogonal factors that sometimes the only trustworthy quantifier is workload benchmarking.

If you're asking whether that 5Ghz is different than this 5Ghz, the main easy answer IPC (instructions per clock). Unfortunately there are no official IPC numbers, but every new release comes with vague unlabeled slides showing %increase, and then reviewres do their pinning the CPU at a specific clock and measure single-threaded performance to estimate relative IPC improvements (like this https://www.guru3d.com/articles-pages/core-i9-12900k-review,...)

If we go into multi-threaded workloads like compilation, then of course the new one completely throws the 8700k out of the water.

But please don't feel pressured to get on the latest and greatest bandwagon, I'm right here running around with a Thinkpad T460s (with a little bit of a need to upgrade).

_Usually_, if you are not waiting for your computer while CPU is on +90% utilization, there should be little gained from a CPU upgrade. (Workloads that depend heavily on cache size or memory latency are counter-examples)

"Unfortunately there are no official IPC numbers"

Nor can there really be. IPC varies pretty wildly, and depends a LOT on optimization for a particular CPU architecture. The instruction mix should match the CPU model's execution units in addition to not having any dependency stalls.

I once compiled a list of architectures’ relative IPC on the SPECINT 2006 benchmark:

  Cortex-A73 (ARMv8-A)  64.4
  Pentium M   69.0
  Bulldozer (AMD FX)  76.2
  K10 (Phenom II)   76.7
  Goldmont Plus (Atom 2nd gen) 77.5
  Core    80.0
  Bobcat    81.3
  Nehalem    90.0
  Jaguar (PS4)   93.5
  Sandy Bridge  100.0
  Tremont (Atom 3rd gen) 100.7
  Ivy Bridge  105.8
  Cortex-A76 (ARMv8.2-A) 114.7
  Zen   115.9
  Haswell   117.6
  Zen+   119.3
  Broadwell  121.5
  Skylake   124.0
  Zen 2   139.8
  A10 (ARMv8.1-A)  139.8
  Cortex-A77 (ARMv8.2-A) 141.0
  Sunny Cove Ice Lake 146.3
  Cypress Cove Rocket Lake 147.6
  Zen 3   167.4
  A11 (ARMv8.2-A)  186.0
  A12 (ARMv8.3-A)  213.8
  A13 (ARMv8.4-A)  235.0
  A14/M1 (ARMv8.5-A) 236.7

Really highlights the absolutely massive gap between Apple Silicon and Cortex/the-rest-of-ARM. Although you'd really want to classify which Cortex SoCs you're using in that list, as implementers love to chop off the L2 & L3 caches to save die space. This is how we ended up with the bigger.big.little configurations - the "biggest" CPU is just the full CPU with all the caches it was supposed to have had.

Known-(very-)naive question: how and why is the M1 so far beyond both the-rest-of-ARM and both Intel (236.7-(Rocket Lake=147.6)=89.1) and AMD? ((236.7-(Zen 3=163.4)=73.3)?

Of course the technically correct answer I'm not looking for is "because Apple optimized it better" :D, I'm looking more at the (obviously probably extrpolated/guessed) path they took to get there. For example perhaps the increased memory bandwidth contributed (ie $pc go brrrrt :P) but like... this is like the elephant in the room that Apple is basically The Best™ ARM shop in town right now, and I guess I'm trying to reason both about the engineering (how Apple got to where they are now) and the market reaction (how Apple and everyone else are going to go forward).

That IPC figure is a bit misleading because different designs clock differently, for example the Apple designs likely have shorter pipelines which uses cycles and power more efficiently but won't support higher clock speeds. I doubt an M1 could hit 7.8GHz no matter how much cooling you gave it, but the Intel design will never be as energy efficient. Apple has different manufacturing constraints because vertical integration likely lets them spend more on the dies, they are using better fabs, etc. Meanwhile they prioritize having very few variants in a way Intel doesn't (or from another standpoint can't because they need more SKUs to sell). The engineers who do this stuff are living in 100-dimensional tradeoff land though, unlike what popular tech rants tend to imply there are no free lunches.

At a higher level it is just hard to do designs at this complexity so the dominating factor is budget divided by how many different products the team needs to make. Intel is the outlier, they managed to sabotage their own dominant position, but across the rest of the CPU world this holds true.

At very least Apple have the process budget and dollar budget to have really expensive DRAM, huge caches, and huge pipeline/big buffers (big ROB etc.)

It’s described in detail at Anandtech [1][2]. It has mostly to do with the fact that Apple’s chips are so much larger in every way measurable. There’s no magic, just raw performance from comparably massively over engineered designs. At the time of its release their reorder buffer had 630 entries vs Intel’s 352 and AMD’s 256. The floating point units inside the cores could handle quadruple of Intel’s throughput per clock. Etc. Etc.

[1]: https://www.anandtech.com/show/16226/apple-silicon-m1-a14-de...

[2]: https://www.anandtech.com/show/16192/the-iphone-12-review/2

Is this compiled from one source or (say) from individual anandtech bnenchmark results? I just say this to ask if there is repeated readings.

It’s compiled from Anandtech benchmarks and archived forum posts. Unfortunately I didn’t write down each source.

Amazing how much better the M1 is relative to Intel's offerings. I notice that this list doesn't include Intel's latest core (Golden Cove). Do you have those benchmarks?

At the time I compiled it Golden Cove wasn’t out yet. Golden Cove has 19% higher IPC than Rocket Lake which would place it just above Zen 3 at a score of 175.6.

Thank you.

So my real question is: will I see a noticeable improvement when playing games? Especially World of Warcraft, which is a super old codebase that relies heavily on cpu.

I have a 3090 as my GPU which is overkill for WoW so I’m mostly wondering about whether the single-threaded performance of the new chip at 5GHz will be much more than my current chip, given that it’s running at 5GHz vs. the default 3.7GHz.

The new gen of Intel chips is somewhat notable because despite AMD fanboys (that's what they are) saying hurr-durr TDP they are very efficient gaming chips (i.e. realistic workloads), so yes it will be a win. They are absolute monsters on a single-thread. Might be worth waiting for Zen4 / raptor lake, at very least for a price drop.

I really doubt you will experience any improvement.

What kind of noticeable improvement do you expect? Are you below 60fps today? Are you waiting for game to load? Do you want to upgrade from 1080 to 4K?

Basically, what is your bottleneck? If you don’t have any visible such, what’s left to improve? I was under the impression WoW was so old that any gaming rig from the last decade would have no problem to run it.

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