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Both AMD and Intel are competing for bragging rights, but they are both pushing the power envelope to accomplish it. The Raptor Lake processors take it to the n

Both AMD and Intel are competing for bragging rights, but they are both pushing the power envelope to accomplish it. The Raptor Lake processors take it to the next level. The law of diminishing returns kicks in whenever a new version is something like 20% faster but requires 25% more power in order to do it. There are times when I will certainly sacrifice cost for speed, but most of the time I want my CPU to churn out pretty good performance while being frugal on the power budget.

machinekob 4y ago
Yea this generation power limiting in bios will be a must for high end. Both 7950X and 13900k don't lose much performance from limiting power to "reasonable" wattage.
- neogodless 4y ago
  Seeing what the 7950X does even when limited to 65W is pretty exciting, and it will be very interesting to see what AMD does with their mobile line of processors come January!
  - brokenmachine 4y ago
    What does limiting the power usage do to the single core performance?
neogodless 4y ago
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.
gibspaulding 4y ago
I've been thinking about these tradeoffs lately. There's an argument one hears that you can "future proof" by buying top of the line and then not having to upgrade as often. I think that's always been a bit flawed, but it feels like with the massive thermal tradeoffs these top end parts are making it less true than ever.
- sliken 4y ago
  Heh, don't think that ever made sense. When a machine is 5 years old you don't particularly care if it's the low, mid, or high end CPU, they are all slow. However not buying ram is a killer and often results in replacing a perfectly good machines.
  - vladvasiliu 4y ago
    I don't fully agree. My 9-year-old 3rd gen Xeon is still plenty usable, barely slower than a "normal" i5 10th gen for doing Rust dev. My work PC with a 4th gen i5 has been unusable even for basic tasks for a few years, despite the 16 GB of RAM and SSD drive. Even moving windows around and stuff is sluggish.
KennyBlanken 4y ago
> Both AMD and Intel are competing for bragging rights, but they are both pushing the power envelope to accomplish it. Yes and no. AMD just released the 5800X3D which is just a teensy bit slower than Intel's top-dog...but it uses a bit more than one third the power the I9-12900KS and 13900K do. Right now you can get a blisteringly-fast (for gaming and other certain specific workloads) AMD CPU with power consumption a skooch over 100W. It yields a nearly 25% increase in framerate on some games, which is huge, and does it at less power usage than the non-stacked-cache variant: https://youtu.be/hBFNoKUHjcg?t=515 https://youtu.be/hBFNoKUHjcg?t=515 You're right about the next generation of Ryzen processors using more power, but nobody knows how much, partly because AMD using some silly nonsense to calculate "TDP", and review units aren't out yet: https://youtu.be/hVnJbiYOCq4?t=363 https://youtu.be/hVnJbiYOCq4?t=363
- neogodless 4y ago
  The Ryzen 7 5800X3D was released in early April 2022. It's rated for a 105W TDP, and draws up to about 190-195W depending on workload[0]. In 1080p gaming (useful for exaggerating the CPU bottleneck), the 13900K outperforms the 5800X3D by about 11%[1]. Review units of "next generation of Ryzen processors" have been out since late September when they became available to buy, so you can read reviews and find out their actual power usage[2]. The Ryzen 9 7950X is shown to push system power consumption up to 355W while running Blender. (TechSpot reviews linked simply because they include power consumption in their reviews.) [0] https://www.techspot.com/review/2449-amd-ryzen-5800x3D/ https://www.techspot.com/review/2449-amd-ryzen-5800x3D/ [1] https://www.techspot.com/review/2552-intel-core-i9-13900k/ https://www.techspot.com/review/2552-intel-core-i9-13900k/ [2] https://www.techspot.com/review/2535-amd-ryzen-7950x/ https://www.techspot.com/review/2535-amd-ryzen-7950x/
  - LegitShady 4y ago
    if youre buying a 13900 for 1080p gaming youre throwing away money anyways. ltt includes the 5800x3d in their numbers for comparisons at resolutions people buying super high end cpus actully want to drive. At idle, where the cpu spends most of it's time, the Intel chips are winning significantly.
PragmaticPulp 4y ago
> The law of diminishing returns kicks in whenever a new version is something like 20% faster but requires 25% more power in order to do it. How often do you run your CPU at 100% load across all cores? For me, idle power draw dominates my overall power consumption. The difference between a 100W peak CPU and a 300W peak CPU basically doesn’t matter across the course of my day, because even compiling large codebases doesn’t last very long. I say this because I bought into the AMD efficiency hype a few years ago, ditching my Intel workstation for an AMD workstation. Yet according to my home energy monitor, my office circuit consumption actually went up, not down. Further investigation revealed that my AMD desktop had significantly higher idle power than the old Intel one. Given that most of my day is spent typing, not pegging the CPU at full load, this nets out to higher overall power consumption. So I’m back to not caring about peak power consumption. If the Intel CPU wants to pull 300W for the 60 seconds that my compile takes, go for it. What I’ll really be looking at is the idle power usage.
- neogodless 4y ago
  Yes. For my desktop, I only care if it's possible to make it quiet overall. For a laptop, I care about performance given the more restrictive cooling restraints of the form factor, and battery life (but that's secondary since I can usually use it plugged in anyway.) So efficiency matters (including under load), but it can't be your only deciding factor in deciding what to buy and use.
- mijamo 4y ago
  If you play any game then it's really not 60 seconds. And then having a processor drawing this kind of power has impact on you PDU, cooling system, case... mATX for instance makes nearly no sense with that kind of power use. But who wants a huge tower on their desk anymore?
  - fomine3 4y ago
    Gamers love BIG RGB TOWER on the desk, isn't it?
- cypress66 4y ago
2OEH8eoCRo0 4y ago
It's a desktop chip, why do we care? If I need the compute power I couldn't care less about power consumption or heat. The thing will mostly sit idle anyway and sip a tiny fraction of that. It seems to me like people only care about peak power consumption when AMD and Apple win those benchmarks.
DigitallyFidget 4y ago
GPUs are doing the same thing. Every generation does bring more efficiency, but also includes an increase of power consumption. I'd like to see a line that aims to reduce power consumption by a meager amount (1-5%) each generation, while continuing to push performance higher and just be an "Energy Efficient" model. Like here's our baseline.. 6 core, 12 threads @ 5.2GHz, let's see how power efficient we can get those specs over the next 5 generations, and how much performance increase we can also squeeze without drawing more power or making it bigger.

machinekob 4y ago

Yea this generation power limiting in bios will be a must for high end. Both 7950X and 13900k don't lose much performance from limiting power to "reasonable" wattage.

neogodless 4y ago
Seeing what the 7950X does even when limited to 65W is pretty exciting, and it will be very interesting to see what AMD does with their mobile line of processors come January!
- brokenmachine 4y ago
  What does limiting the power usage do to the single core performance?

neogodless 4y ago

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.

gibspaulding 4y ago

I've been thinking about these tradeoffs lately. There's an argument one hears that you can "future proof" by buying top of the line and then not having to upgrade as often. I think that's always been a bit flawed, but it feels like with the massive thermal tradeoffs these top end parts are making it less true than ever.

sliken 4y ago
Heh, don't think that ever made sense. When a machine is 5 years old you don't particularly care if it's the low, mid, or high end CPU, they are all slow. However not buying ram is a killer and often results in replacing a perfectly good machines.
- vladvasiliu 4y ago
  I don't fully agree. My 9-year-old 3rd gen Xeon is still plenty usable, barely slower than a "normal" i5 10th gen for doing Rust dev. My work PC with a 4th gen i5 has been unusable even for basic tasks for a few years, despite the 16 GB of RAM and SSD drive. Even moving windows around and stuff is sluggish.

KennyBlanken 4y ago

> Both AMD and Intel are competing for bragging rights, but they are both pushing the power envelope to accomplish it. Yes and no. AMD just released the 5800X3D which is just a teensy bit slower than Intel's top-dog...but it uses a bit more than one third the power the I9-12900KS and 13900K do. Right now you can get a blisteringly-fast (for gaming and other certain specific workloads) AMD CPU with power consumption a skooch over 100W. It yields a nearly 25% increase in framerate on some games, which is huge, and does it at less power usage than the non-stacked-cache variant: https://youtu.be/hBFNoKUHjcg?t=515 https://youtu.be/hBFNoKUHjcg?t=515 You're right about the next generation of Ryzen processors using more power, but nobody knows how much, partly because AMD using some silly nonsense to calculate "TDP", and review units aren't out yet: https://youtu.be/hVnJbiYOCq4?t=363 https://youtu.be/hVnJbiYOCq4?t=363

neogodless 4y ago
The Ryzen 7 5800X3D was released in early April 2022. It's rated for a 105W TDP, and draws up to about 190-195W depending on workload[0]. In 1080p gaming (useful for exaggerating the CPU bottleneck), the 13900K outperforms the 5800X3D by about 11%[1]. Review units of "next generation of Ryzen processors" have been out since late September when they became available to buy, so you can read reviews and find out their actual power usage[2]. The Ryzen 9 7950X is shown to push system power consumption up to 355W while running Blender. (TechSpot reviews linked simply because they include power consumption in their reviews.) [0] https://www.techspot.com/review/2449-amd-ryzen-5800x3D/ https://www.techspot.com/review/2449-amd-ryzen-5800x3D/ [1] https://www.techspot.com/review/2552-intel-core-i9-13900k/ https://www.techspot.com/review/2552-intel-core-i9-13900k/ [2] https://www.techspot.com/review/2535-amd-ryzen-7950x/ https://www.techspot.com/review/2535-amd-ryzen-7950x/
- LegitShady 4y ago
  if youre buying a 13900 for 1080p gaming youre throwing away money anyways. ltt includes the 5800x3d in their numbers for comparisons at resolutions people buying super high end cpus actully want to drive. At idle, where the cpu spends most of it's time, the Intel chips are winning significantly.

PragmaticPulp 4y ago

> The law of diminishing returns kicks in whenever a new version is something like 20% faster but requires 25% more power in order to do it. How often do you run your CPU at 100% load across all cores? For me, idle power draw dominates my overall power consumption. The difference between a 100W peak CPU and a 300W peak CPU basically doesn’t matter across the course of my day, because even compiling large codebases doesn’t last very long. I say this because I bought into the AMD efficiency hype a few years ago, ditching my Intel workstation for an AMD workstation. Yet according to my home energy monitor, my office circuit consumption actually went up, not down. Further investigation revealed that my AMD desktop had significantly higher idle power than the old Intel one. Given that most of my day is spent typing, not pegging the CPU at full load, this nets out to higher overall power consumption. So I’m back to not caring about peak power consumption. If the Intel CPU wants to pull 300W for the 60 seconds that my compile takes, go for it. What I’ll really be looking at is the idle power usage.

neogodless 4y ago
Yes. For my desktop, I only care if it's possible to make it quiet overall. For a laptop, I care about performance given the more restrictive cooling restraints of the form factor, and battery life (but that's secondary since I can usually use it plugged in anyway.) So efficiency matters (including under load), but it can't be your only deciding factor in deciding what to buy and use.
mijamo 4y ago
If you play any game then it's really not 60 seconds. And then having a processor drawing this kind of power has impact on you PDU, cooling system, case... mATX for instance makes nearly no sense with that kind of power use. But who wants a huge tower on their desk anymore?
- fomine3 4y ago
  Gamers love BIG RGB TOWER on the desk, isn't it?
cypress66 4y ago

2OEH8eoCRo0 4y ago

It's a desktop chip, why do we care? If I need the compute power I couldn't care less about power consumption or heat. The thing will mostly sit idle anyway and sip a tiny fraction of that. It seems to me like people only care about peak power consumption when AMD and Apple win those benchmarks.

DigitallyFidget 4y ago

GPUs are doing the same thing. Every generation does bring more efficiency, but also includes an increase of power consumption. I'd like to see a line that aims to reduce power consumption by a meager amount (1-5%) each generation, while continuing to push performance higher and just be an "Energy Efficient" model. Like here's our baseline.. 6 core, 12 threads @ 5.2GHz, let's see how power efficient we can get those specs over the next 5 generations, and how much performance increase we can also squeeze without drawing more power or making it bigger.