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I do think TechSpot[0] (aka Hardware Unboxed) has a good chart[1] that highlights some differences in power consumption utilized to achieve performance. Notice

I do think TechSpot[0] (aka Hardware Unboxed) has a good chart[1] that highlights some differences in power consumption utilized to achieve performance. Notice at 185W, the Ryzen 9 7950X is churning out about 36% higher performance than the Core i9 13900K. The Intel CPU, however, is then able to continue drawing up to 335W! At their respective peak scores, the i9 is using over 70% more power. [0] https://www.techspot.com/review/2552-intel-core-i9-13900k/ https://www.techspot.com/review/2552-intel-core-i9-13900k/ [1] https://static.techspot.com/articles-info/2552/bench/Power_Scaling_AMD-p.webp https://static.techspot.com/articles-info/2552/bench/Power_S...

nezirus 4y ago
I'm mostly interested in numbers under 100W, maybe even 65W, since I plan to down-clock my (future) Zen 4 machine. AMD is killing it with efficiency there.
- neogodless 4y ago
  Yes - comparing the above 65W score from AMD to Intel's 145W score highlights the stark difference!
- sliken 4y ago
  I've seen several posts showing that the most minor of underclocks and undervolts produce substantial power savings and minimal performance differences. Apparently Intel's trying really hard on an old process to get the performance crown, forcing AMD to clock higher than they'd like to compete. It's ridiculous that they double the power for 10% performance. But the nice thing is you can half the power and take the 10% hit. Also note that the 7900/7900X are dual chiplet design that has a significant power impact. The 7700x and below have a single chiplet and saves power, and also increases single thread perf. If you look at the gaming benchmarks the 7700x is often better than the 7900x, not to mention all the Intel chips except the top of the line i9. So if you buy the 7700x and underclock just a bit you should have a very efficient desktop.
  - neogodless 4y ago
    > the 7900/7900X are dual chiplet design This is a minor terminology mix-up. The term you want here is "CCX". Each CCX holds multiple chiplets. See https://www.tomshardware.com/reviews/amd-ccx-definition-cpu-core-explained,6338.html https://www.tomshardware.com/reviews/amd-ccx-definition-cpu-... for more details. EDIT: It does look like my own information on this was rusty. A "chiplet" is not an individual core, but a trimmed down die that does not have a memory controller. A "CCX" contains cores (within a chiplet) and L3 cache. https://www.hardwaretimes.com/amd-ccd-and-ccx-in-ryzen-processors-explained/ https://www.hardwaretimes.com/amd-ccd-and-ccx-in-ryzen-proce... > The basic unit of a Ryzen processor is a CCX or Core Complex, a quad-core/octa-core CPU chiplet with a shared L3 cache.
    - rektide 4y ago
      > For the Ryzen 3000-series processors, CCX refers to a four-core grouping inside of each core chiplet die (CCD). For example, an AMD CPU with 8 cores will have a CCD with two 4-core CCXs. From that link, your statement does not appear accurate. Multiple CCX's appear on a given Core Chiplet Die. There are indeed two vs one core chiplets on different Ryzen designs (plus the IOD).
- sailplease 4y ago
  check out https://arstechnica.com/gadgets/2022/10/intel-i9-13900k-and-i5-13600k-review-beating-amd-at-its-own-game/ https://arstechnica.com/gadgets/2022/10/intel-i9-13900k-and-... - they power limited both 7000 and raptor lake models and surprisingly, amd doesn't respect the power limits - at 65W it's burning 90W and intel is respecting the 65W limit, 7.868Whr vs 8.58Whr to complete the same task (h264 encoding in handbrake), so interestingly intel on a 2 node disadvantage is more power efficient if you set your power limits.
KingOfCoders 4y ago
but I do think Raptor lake consunes less power than Zen4 when idling e.g. web browsing, code editing etc. I would want to see power usage for VS code + Firefox etc. I use high performance only for seconds when compiling.
- selectodude 4y ago
  Zen's idle performance is absolutely atrocious due to the I/O die that constantly draws 20 watts. Pretty sure Intel's stuff in total draws less than half that.
  - Melatonic 4y ago
    Intel invested a crapload of money in laptop CPU's and low idle which is one of the reason they dominated that market for so long - I would guess that it bled over into desktop as well.
  - sliken 4y ago
    Are you talking about last years zen3? That was a common complaint. From https://www.tweaktown.com/reviews/10195/amd-ryzen-5-7600x-zen-4-cpu/index.html https://www.tweaktown.com/reviews/10195/amd-ryzen-5-7600x-ze... "Power consumption is measured directly from the dual eight-pin connections. At peak, the 7600X pulls an impressive 130W, and during idle, it was down to 18w." Sounds pretty good, especially considering its at the "dual eight-pin" power supply connection. Not laptop class, but pretty good for a high performance desktop.
    - neogodless 4y ago
      Anecdotally, my Zen 3 5900X rated at 105W TDP, sitting kind of idle (with a dozen or so programs open, task manager showing 1% usage) is drawing about 11W.
      - sliken 4y ago
        I do seem to recall a AGESA update (motherboard firmware) that did managed to reduce the IOD power usage when idle. Sad that it was months after most of the reviews came out.
jeffbee 4y ago
That techspot review triggers me. Why does the guy go on and on about how impractical the 13900 is compared to the 12900, since the 13900 is "throttling"? Yeah, the 13900K hits a steady state of 5300MHz with all cores active and stays that way forever, which is great! The apparently "more practical" 12900K hits 4900MHz on all cores and does the job slower but it's "not throttling". This makes zero sense. The popular tech press understanding of how closed-loop control systems work is just REALLY annoying.
ksec 4y ago
And it is important to remember the AMD IOD is still on N6 or similar to current Intel 7 2nd gen. ( i.e On I/O level AMD and Intel are on the same Node ) Even if Intel was on Intel 5 or TSMC N5 equivalent it still likely wouldn't be using similar power as AMD. So I am actually surprised at how well AMD Zen 4 is doing. It used to be if you want MT you go with AMD, at the expense of ST. Now this is no longer the case. If you care about energy efficiency, just buy AMD Zen 4.
- tails4e 4y ago
  I think this mix of processes is testament to the fact analog is not scaling, and high speed IO has a lot of analog/phys. So having an IOD on 3nm would cost more and probably consume similar power, at least for the phys. Of course you will always get sub systems on that die that would benefit, but overall its likely a net loss.
fomine3 4y ago
Benchmark with same power limit like this is what I'd like to know. I also want to know wall watt usage for them, to verify it's limited correctly, and how much chipset/other components uses power.
- neogodless 4y ago
  See this comment: https://news.ycombinator.com/item?id=33278470 https://news.ycombinator.com/item?id=33278470 Not sure if it gets closer to the testing approach you're looking for?
  - fomine3 4y ago
    This is great but I also want kill-a-watt measurement
neoyagami 4y ago
how costly is in the US that diference (of power consumption) in a year?

nezirus 4y ago

I'm mostly interested in numbers under 100W, maybe even 65W, since I plan to down-clock my (future) Zen 4 machine. AMD is killing it with efficiency there.

neogodless 4y ago
Yes - comparing the above 65W score from AMD to Intel's 145W score highlights the stark difference!
sliken 4y ago
I've seen several posts showing that the most minor of underclocks and undervolts produce substantial power savings and minimal performance differences. Apparently Intel's trying really hard on an old process to get the performance crown, forcing AMD to clock higher than they'd like to compete. It's ridiculous that they double the power for 10% performance. But the nice thing is you can half the power and take the 10% hit. Also note that the 7900/7900X are dual chiplet design that has a significant power impact. The 7700x and below have a single chiplet and saves power, and also increases single thread perf. If you look at the gaming benchmarks the 7700x is often better than the 7900x, not to mention all the Intel chips except the top of the line i9. So if you buy the 7700x and underclock just a bit you should have a very efficient desktop.
- neogodless 4y ago
  > the 7900/7900X are dual chiplet design This is a minor terminology mix-up. The term you want here is "CCX". Each CCX holds multiple chiplets. See https://www.tomshardware.com/reviews/amd-ccx-definition-cpu-core-explained,6338.html https://www.tomshardware.com/reviews/amd-ccx-definition-cpu-... for more details. EDIT: It does look like my own information on this was rusty. A "chiplet" is not an individual core, but a trimmed down die that does not have a memory controller. A "CCX" contains cores (within a chiplet) and L3 cache. https://www.hardwaretimes.com/amd-ccd-and-ccx-in-ryzen-processors-explained/ https://www.hardwaretimes.com/amd-ccd-and-ccx-in-ryzen-proce... > The basic unit of a Ryzen processor is a CCX or Core Complex, a quad-core/octa-core CPU chiplet with a shared L3 cache.
  - rektide 4y ago
    > For the Ryzen 3000-series processors, CCX refers to a four-core grouping inside of each core chiplet die (CCD). For example, an AMD CPU with 8 cores will have a CCD with two 4-core CCXs. From that link, your statement does not appear accurate. Multiple CCX's appear on a given Core Chiplet Die. There are indeed two vs one core chiplets on different Ryzen designs (plus the IOD).
sailplease 4y ago
check out https://arstechnica.com/gadgets/2022/10/intel-i9-13900k-and-i5-13600k-review-beating-amd-at-its-own-game/ https://arstechnica.com/gadgets/2022/10/intel-i9-13900k-and-... - they power limited both 7000 and raptor lake models and surprisingly, amd doesn't respect the power limits - at 65W it's burning 90W and intel is respecting the 65W limit, 7.868Whr vs 8.58Whr to complete the same task (h264 encoding in handbrake), so interestingly intel on a 2 node disadvantage is more power efficient if you set your power limits.

KingOfCoders 4y ago

but I do think Raptor lake consunes less power than Zen4 when idling e.g. web browsing, code editing etc. I would want to see power usage for VS code + Firefox etc. I use high performance only for seconds when compiling.

selectodude 4y ago
Zen's idle performance is absolutely atrocious due to the I/O die that constantly draws 20 watts. Pretty sure Intel's stuff in total draws less than half that.
- Melatonic 4y ago
  Intel invested a crapload of money in laptop CPU's and low idle which is one of the reason they dominated that market for so long - I would guess that it bled over into desktop as well.
- sliken 4y ago
  Are you talking about last years zen3? That was a common complaint. From https://www.tweaktown.com/reviews/10195/amd-ryzen-5-7600x-zen-4-cpu/index.html https://www.tweaktown.com/reviews/10195/amd-ryzen-5-7600x-ze... "Power consumption is measured directly from the dual eight-pin connections. At peak, the 7600X pulls an impressive 130W, and during idle, it was down to 18w." Sounds pretty good, especially considering its at the "dual eight-pin" power supply connection. Not laptop class, but pretty good for a high performance desktop.
  - neogodless 4y ago
    Anecdotally, my Zen 3 5900X rated at 105W TDP, sitting kind of idle (with a dozen or so programs open, task manager showing 1% usage) is drawing about 11W.
    - sliken 4y ago
      I do seem to recall a AGESA update (motherboard firmware) that did managed to reduce the IOD power usage when idle. Sad that it was months after most of the reviews came out.

jeffbee 4y ago

That techspot review triggers me. Why does the guy go on and on about how impractical the 13900 is compared to the 12900, since the 13900 is "throttling"? Yeah, the 13900K hits a steady state of 5300MHz with all cores active and stays that way forever, which is great! The apparently "more practical" 12900K hits 4900MHz on all cores and does the job slower but it's "not throttling". This makes zero sense. The popular tech press understanding of how closed-loop control systems work is just REALLY annoying.

ksec 4y ago

And it is important to remember the AMD IOD is still on N6 or similar to current Intel 7 2nd gen. ( i.e On I/O level AMD and Intel are on the same Node ) Even if Intel was on Intel 5 or TSMC N5 equivalent it still likely wouldn't be using similar power as AMD. So I am actually surprised at how well AMD Zen 4 is doing. It used to be if you want MT you go with AMD, at the expense of ST. Now this is no longer the case. If you care about energy efficiency, just buy AMD Zen 4.

tails4e 4y ago
I think this mix of processes is testament to the fact analog is not scaling, and high speed IO has a lot of analog/phys. So having an IOD on 3nm would cost more and probably consume similar power, at least for the phys. Of course you will always get sub systems on that die that would benefit, but overall its likely a net loss.

fomine3 4y ago

Benchmark with same power limit like this is what I'd like to know. I also want to know wall watt usage for them, to verify it's limited correctly, and how much chipset/other components uses power.

neogodless 4y ago
See this comment: https://news.ycombinator.com/item?id=33278470 https://news.ycombinator.com/item?id=33278470 Not sure if it gets closer to the testing approach you're looking for?
- fomine3 4y ago
  This is great but I also want kill-a-watt measurement

neoyagami 4y ago

how costly is in the US that diference (of power consumption) in a year?