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You can set lower power limits for both AMD and Intel's chips to improve perf/watt. AMD benefits more than Intel when doing so. Here's some more reading if you

• nottorp 4y ago
  I can and I have. There's a ryzen limited to 70 W in the bios under my desk :) 99.99% of the population doesn't know this option exists. And 0.01% want BIGGER NUMBERS OMG 720FPS!!! and ruin power consumption worldwide for everyone else.
  • sliken 4y ago
    I blame Intel for that. They pushed the clock speed high for silly small perf gains. AMD could take the high road, then media would brag about how fast Intel is and AMD would lose market share.
    • MrFoof 4y ago
      Indeed. The game Intel used to play is now the game everyone plays -- Intel, AMD, and NVIDIA, for both consumer CPUs and GPUs. At least on the desktop. They tend to run them to redline by default, because numbers. It's all about getting that big splash at launch, to ride it for higher average sale price as long as possible. Which is unfortunate, because when it comes to benchmarks, understanding the context of a test setup is extraordinarily important. Are you buying that very high-end memory the test setup used and then manually adjusting timings? No? Then you're not getting those numbers. Heck, you may be losing 20% or more performance compared to the test rig on just the difference in memory. Never mind adjusting other things, ensuring the system's thermals are entirely kept in check to prevent throttling, etc.
    • snvzz 4y ago
      >AMD could take the high road, then media would brag about how fast Intel is and AMD would lose market share. This already happened in previous generations (especially Zen2). AMD has to play this stupid game, unfortunately, because the press is what it is.
    • midoridensha 4y ago
      >I blame Intel for that. As you should. I worked at Intel back in the 00s when they were in the "megahertz wars". All they talked about internally was "we're winning the MHz wars!!! Yay!". When anyone mentioned power consumption, or how fucking loud the cooling fans were, or MIPS/Watt, they didn't care; all that mattered was MHz. Hitching their wagon to RAMBUS memory was part of this. Then they got pissed and indignant when consumers didn't want to spend a fortune on RAMBUS memory and bought AMD CPUs with cheap SDRAM instead.
      • sliken 4y ago
        That fits. The p4 had a long pipeline, high clock speed, and poor perf per MHz. AMD pushed the general performance score, forget the name, and seems like the succeeded. Doubly so since they shipped x86-64 first, which people did care about. I wrote a few microbenchmarks to explore the performance promises of rambus, and didn't find anything.
  • ncann 4y ago
    What is this option? I would like to know more about it.
• sliken 4y ago
  My summary is AMD is hurt MUCH less than Intel by lowering the power. One example from the article: Cinebench R23 multithread: Ryzen 7950X 230 -> 125 watts = 95% Ryzen 7950X 230 -> 105 watts = 93% Ryzen 7950X 230 -> 65 watts = 81% Intel I9-13900k 253 watts -> 125 watts = 78% Intel I9-13900k 253 watts -> 105 watts = 72% Intel I9-13900k 253 watts -> 65 watts = 56% Other benchmarks like C-ray show ZERO slowdown going from 230 -> 125 and even 105 watts. Intel drops by 21% for 125 watts and 30% for 105 watts. Personally I'd rather get the 7900X (or non-x) and you'd keep an even larger fraction of the performance within a given power limit. It's pretty clear who has the worse core and has to push harder into high clock/terrible power usage for not much gain curve.
  • mtlmtlmtlmtl 4y ago
    I'm a little dubious of benchmarks that compare only one pair of chips when it comes to details like power efficiency and tweaking. The silicon lottery can make a big difference.
    • sliken 4y ago
      Sure. Various forums corroborate the reducing the Ryzen 7000 series at 65 TDP is often a less than 10% decrease in performance. Also keep in mind that "performance mode" on Intel can significantly increase the default 253 watt TDP. Anandtech reviews of the i9-13900k hit 380 watts I believe. So sure there's chip to chip variation, but generally the AMD chips are more power efficient and have much lower penalties for reducing the TDP.
      • inawarminister 4y ago
        Do you know how to undervolt laptop Ryzens? I'm really interested if we can increase the battery life by another 30-40% or so
        • scheme271 4y ago
          The easiest way is to go to the bios or cpu settings and change the precision optimizer so that you have a negative pbo setting. That'll reduce the stock voltage at a given frequency. It'll also potentially speed your chip up since this lets the chip boost to higher frequencies at a given power level. I think the lowest you can go is -30, but try -20 or so and see if your system is stable before trying lower values.
• joveian 4y ago
  You can set various power settings that suggest that they are limits, but at least in the Skylake NUC I have they really don't do much and certainly don't limit the maximum power the system uses at all. The article doesn't talk enough about the actual power use vs the settings although it sounds like while both are going over there might actually be some limiting in the recent chips.
  • sagarm 4y ago
    That Anandtech article did include some power measurements on page three, but given those measurements show the limits are applied inconsistently between AMD and Intel it would have been nice to have power measurements on other graphs too.