6 ms·

everything xen https://youtu.be/Ps317u9Rhl0?t=62 https://youtu.be/Ps317u9Rhl0?t=62 ! Almost doubling the TDP for a 25%-30% frequency increase isn't doing most

everything xen https://youtu.be/Ps317u9Rhl0?t=62 https://youtu.be/Ps317u9Rhl0?t=62 ! Almost doubling the TDP for a 25%-30% frequency increase isn't doing most any good (appeals mainly to benchmark obsessed folks with poor sense of scale). But it's the game that marketing people have to play---so hence the 105 watt X-variants. When I upgrade to AM5 I'll go with 65W no doubt.

automatic6131 4y ago
>appeals mainly to benchmark obsessed folks with poor sense of scale I resemble this remark. But I will not change :-)
7speter 4y ago
The competition (Intel) allows them to do this considering their k cpus have a tdp of what? 125w? People are still buying Intel so might as well try and convince them that AMD is just as "fast"
- doommius 4y ago
  my 10900k uses like 200-250 watt when it´s pushed. The newer 13900k has PL1/PL2 power limits of 125W and 253W, even then it has peaks of 350 watt from what I can read.
  - silon42 4y ago
    Wow. And I'm unhappy with laptops that require more than 60W USB-C PD.
justsomehnguy 4y ago
> When I upgrade to AM5 I'll go with 65W no doubt Since C2D days anything over 65W provided diminishing results for a regular user. But then you can't participate in the di^W gigaherz measuring party.
- gcatalfamo 4y ago
  Agree, but I honestly can't fathom the productivity/gaming benefits of the X models compared to such difference in power draw compared to the "regular" 7900
  - ilyt 4y ago
    Gaming performance will be dominated by watts of your GPU tbh.
    - tehbeard 4y ago
      For the shiny shiny "AAA" releases, sure. There's plenty of 4X / RTS / Simulation games where the CPU will be the bottleneck.
      - piaste 4y ago
        And for those games, the X3D series are going to be the gold standard, if they follow up in the footsteps of the 5800X3D. Meaning the X series will be in a bit of an awkward position. Disclosure: I own a 7600X, but strictly because I wanted a new desktop for the Christmas holidays, so I couldn't wait for either the 65W budget option or the X3D high-end (I do play Paradox games a fair bit). Hopefully I'll be able to sell it and upgrade without too much loss, once the full lineup is available.
      - ilyt 4y ago
        Yeah I don't care for extra watts there, I want it run fast
  - dagw 4y ago
    Depends who's paying. 15-30% (or more, if compared to Threadrippers) faster compile times or simulation runs can be a real quality of life improvement in many cases, especially if your employer is paying for it.
em500 4y ago
It should be well known by now that at the high end performance scales very poorly with power consumption (and also with price). (Same reason why you couldn't straightforwardly extrapolate the great laptop performance of Apple's M1 and project them to clobber Intel/AMD on the desktop/server.) But the people who (think that they) really need those extra few % performance also tend to be the ones willing to spend. Personally I think this is fine: the big spenders who buy the top $$$ and TDP parts basically subsidize a lot of the costs for the more price conscious who benefit from all the R&D and still get great performance.
- Dalewyn 4y ago
  I agree. You buy high end parts either to enjoy it or because you truly need it. You don't buy high end parts to be fiscally efficient, efficiency has always been the realm of mid to low end parts. This applies to nearly everything.
  - hayley-patton 4y ago
    It didn't seem that the mid-end was efficient when I last went processor shopping (last June). It appeared that of the Zen 3 processors (which were interesting as I already had an AM4 rest-of-the-computer) only the 5600 and 5900X had "good" prices to me, as the 6-core 5700 was only a bit faster than the 5600 for a fairly large jump in price, and the 8-core 5800 had only two more cores than the former processors, while not being _that_ much cheaper than the 12-core 5900X. Given that I hold onto parts for a while, and that moar cores with shared memory is what I was after (for fuzzing and model checking, mostly[1]) I took the plunge and got the 5900X. Another advantage there was that I would not have to build another computer to use two cheaper processors. But that only works as I don't think I am limited by any other factors like memory or disk bandwidth. I did however limit the processor to a 65W TDP to reduce heat output and power usage, which only slowed down my very parallel programs about 10%, and didn't affect less parallel programs at all. (The duplicated other components of two machines would also draw more power, though perhaps not that much in comparison to processors here.) [1] For a fuzzer you could easily give separate machines multiple random seeds, so really that is no issue. But for model checking/exhaustive search there needs to be a proper form of work distribution. I haven't a clue what the network bandwidth requirement of e.g. TLC, so that might also require faster NICs than one gets on motherboards to not stall processors on the network.
jeswin 4y ago
For my desktop, I value 30% faster compilation far more than I care about the CPU using more watts. It depends on what you do, and it's not all benchmarks.
- mpol 4y ago
  Sure, no problem. Just be aware that the power bill is part of the price too. I used to take the rough calculation; every Watt used 24/7 is 1 Euro per year. That wasn't even true 2 years ago, now it might even be going to 3 or 4 Euro. So a 50 Watt increase can cost up to 200 Euro per year when it is running 24/7. After 3 years, you could have bought quite a different class of CPU at 65 Watt TDP. If you don't run it 24/7, divide the cost by how much you do use it.
  - pedrocr 4y ago
    We could use more benchmarks about idle power usage for that. I'm speccing a new NAS and those are the watts you end up paying 24/7, not power usage at peak. You'd have to be running constant compiles or be a very avid gamer for the peak load to dominate. These parts are just the X parts with a lower power limit after all, they're not a more efficient process or something like that.
    - formerly_proven 4y ago
      Chiplet-based products were never competitive for idle/low load power usage and while Zen 4 improves quite a bit over Zen 2/3, monolithic CPUs will be way superior, regardless of AMD (APU) or Intel. We're seeing the first generation of chiplet-based GPUs and the same thing seems to go for them as well.
  - perihelions 4y ago
    Think about the context. - "I value 30% faster compilation far more than..." It takes 10,000 hours of wall-clock CPU time to reach your 200 euro figure. That tradeoff is against a 30% decrease in compilation time, or 3,000 hours. Say what you will about idle power or whatever; but we're talking about the case of 100% all-core CPU for a programmer who is compiling something, and whether or not they should throttle those CPU cores to save money on power bills. The math is an easy "no".
minimaul 4y ago
I do this even on AM4 - I have a 5800X but I run it in ECO mode which locks it to 65W PTT. Drops on average less than 10% multi core performance and no single core performance at all. Much quieter, cheaper, etc. I also have a 35W 5750GE (8c16t too) and that’s also a very respectable performer compared to the 105W 5800X! We’re so far off the ideal part of the perf/W curve it’s not funny, and I swear being closer to that is part of where Apple et al have done so well. Edit: and from compute benchmarks on my 3090, the best perf/watt - measured in whole system total power drawn to complete a variety of cuda tasks, that card is most efficient around 225W or so… which is crazy considering they’re sold at 350W or more!
PragmaticPulp 4y ago
> Almost doubling the TDP for a 25%-30% frequency increase isn't doing most any good Having 25-30% faster compile times, faster video renders, higher frame rates, snappier responses is huge. I don’t understand why you’re suggesting it’s not doing anyone any good. Our CPUs don’t run at 100% all of the time. If my CPU takes 200W instead of 65W for the small fraction of the day that I’m doing something CPU-intensive, the difference is absolutely negligible. I’m going to use more total power when I cook my dinner, probably. If you are the kind of person willing to give up 1/4 of your performance for slightly lower power consumption under load, then go for those slower chips. You’re not the target market for the premium grade performance parts.
- chaimanmeow 4y ago
  You have some good points, *if* the OS and apps that you are using are designed with care and regard for energy efficiency. In my experience it's often not the case. Edge with its sleeping tabs function is a big improvement and example when app writers do care a bit about not wasting loads of energy. But it's really a very mixed bag. Many browsers do not. And there is plenty of nuissance javascript that will peg the CPU and RAM all day long. If you're a Steam user, you know that almost all games, when you idle them in the background, and even in pause mode, peg one or a few CPU threads as well as the GPU. The problem is greatly reduced for those editing their windows power profiles (or for linux users, cpufreq-set) to have their processors run at reduced frequencies. For those it might justify getting 105W X's over the 65W. Now the almost 30% peak perf gain that the X models can sustain are potentially a big advantage. Yet real life usage speedup isn't as big as one might expect from looking at benchmark multithread compute scores; compiling has a lot of waiting on IO. And the single thread differences between the mellow frequency non-X and the souped up X versions are not very big, percentage wise. So you might get 30% speedup for some cases, but probably more typical difference might closer to ~15%. iGPU throttling is an area where the 65W models would be disadvantaged at, sometimes significantly. So in some cases (workstation type usage), especially if running without a dedicated video card, the 105W choice might admittedly make good sense. 65W vs 105W bottom line: I guess it's a case of YMMV.

automatic6131 4y ago

>appeals mainly to benchmark obsessed folks with poor sense of scale I resemble this remark. But I will not change :-)

7speter 4y ago

The competition (Intel) allows them to do this considering their k cpus have a tdp of what? 125w? People are still buying Intel so might as well try and convince them that AMD is just as "fast"

doommius 4y ago
my 10900k uses like 200-250 watt when it´s pushed. The newer 13900k has PL1/PL2 power limits of 125W and 253W, even then it has peaks of 350 watt from what I can read.
- silon42 4y ago
  Wow. And I'm unhappy with laptops that require more than 60W USB-C PD.

justsomehnguy 4y ago

> When I upgrade to AM5 I'll go with 65W no doubt Since C2D days anything over 65W provided diminishing results for a regular user. But then you can't participate in the di^W gigaherz measuring party.

gcatalfamo 4y ago
Agree, but I honestly can't fathom the productivity/gaming benefits of the X models compared to such difference in power draw compared to the "regular" 7900
- ilyt 4y ago
  Gaming performance will be dominated by watts of your GPU tbh.
  - tehbeard 4y ago
    For the shiny shiny "AAA" releases, sure. There's plenty of 4X / RTS / Simulation games where the CPU will be the bottleneck.
    - piaste 4y ago
      And for those games, the X3D series are going to be the gold standard, if they follow up in the footsteps of the 5800X3D. Meaning the X series will be in a bit of an awkward position. Disclosure: I own a 7600X, but strictly because I wanted a new desktop for the Christmas holidays, so I couldn't wait for either the 65W budget option or the X3D high-end (I do play Paradox games a fair bit). Hopefully I'll be able to sell it and upgrade without too much loss, once the full lineup is available.
    - ilyt 4y ago
      Yeah I don't care for extra watts there, I want it run fast
- dagw 4y ago
  Depends who's paying. 15-30% (or more, if compared to Threadrippers) faster compile times or simulation runs can be a real quality of life improvement in many cases, especially if your employer is paying for it.

em500 4y ago

It should be well known by now that at the high end performance scales very poorly with power consumption (and also with price). (Same reason why you couldn't straightforwardly extrapolate the great laptop performance of Apple's M1 and project them to clobber Intel/AMD on the desktop/server.) But the people who (think that they) really need those extra few % performance also tend to be the ones willing to spend. Personally I think this is fine: the big spenders who buy the top $$$ and TDP parts basically subsidize a lot of the costs for the more price conscious who benefit from all the R&D and still get great performance.

Dalewyn 4y ago
I agree. You buy high end parts either to enjoy it or because you truly need it. You don't buy high end parts to be fiscally efficient, efficiency has always been the realm of mid to low end parts. This applies to nearly everything.
- hayley-patton 4y ago
  It didn't seem that the mid-end was efficient when I last went processor shopping (last June). It appeared that of the Zen 3 processors (which were interesting as I already had an AM4 rest-of-the-computer) only the 5600 and 5900X had "good" prices to me, as the 6-core 5700 was only a bit faster than the 5600 for a fairly large jump in price, and the 8-core 5800 had only two more cores than the former processors, while not being _that_ much cheaper than the 12-core 5900X. Given that I hold onto parts for a while, and that moar cores with shared memory is what I was after (for fuzzing and model checking, mostly[1]) I took the plunge and got the 5900X. Another advantage there was that I would not have to build another computer to use two cheaper processors. But that only works as I don't think I am limited by any other factors like memory or disk bandwidth. I did however limit the processor to a 65W TDP to reduce heat output and power usage, which only slowed down my very parallel programs about 10%, and didn't affect less parallel programs at all. (The duplicated other components of two machines would also draw more power, though perhaps not that much in comparison to processors here.) [1] For a fuzzer you could easily give separate machines multiple random seeds, so really that is no issue. But for model checking/exhaustive search there needs to be a proper form of work distribution. I haven't a clue what the network bandwidth requirement of e.g. TLC, so that might also require faster NICs than one gets on motherboards to not stall processors on the network.

jeswin 4y ago

For my desktop, I value 30% faster compilation far more than I care about the CPU using more watts. It depends on what you do, and it's not all benchmarks.

mpol 4y ago
Sure, no problem. Just be aware that the power bill is part of the price too. I used to take the rough calculation; every Watt used 24/7 is 1 Euro per year. That wasn't even true 2 years ago, now it might even be going to 3 or 4 Euro. So a 50 Watt increase can cost up to 200 Euro per year when it is running 24/7. After 3 years, you could have bought quite a different class of CPU at 65 Watt TDP. If you don't run it 24/7, divide the cost by how much you do use it.
- pedrocr 4y ago
  We could use more benchmarks about idle power usage for that. I'm speccing a new NAS and those are the watts you end up paying 24/7, not power usage at peak. You'd have to be running constant compiles or be a very avid gamer for the peak load to dominate. These parts are just the X parts with a lower power limit after all, they're not a more efficient process or something like that.
  - formerly_proven 4y ago
    Chiplet-based products were never competitive for idle/low load power usage and while Zen 4 improves quite a bit over Zen 2/3, monolithic CPUs will be way superior, regardless of AMD (APU) or Intel. We're seeing the first generation of chiplet-based GPUs and the same thing seems to go for them as well.
- perihelions 4y ago
  Think about the context. - "I value 30% faster compilation far more than..." It takes 10,000 hours of wall-clock CPU time to reach your 200 euro figure. That tradeoff is against a 30% decrease in compilation time, or 3,000 hours. Say what you will about idle power or whatever; but we're talking about the case of 100% all-core CPU for a programmer who is compiling something, and whether or not they should throttle those CPU cores to save money on power bills. The math is an easy "no".

minimaul 4y ago

I do this even on AM4 - I have a 5800X but I run it in ECO mode which locks it to 65W PTT. Drops on average less than 10% multi core performance and no single core performance at all. Much quieter, cheaper, etc. I also have a 35W 5750GE (8c16t too) and that’s also a very respectable performer compared to the 105W 5800X! We’re so far off the ideal part of the perf/W curve it’s not funny, and I swear being closer to that is part of where Apple et al have done so well. Edit: and from compute benchmarks on my 3090, the best perf/watt - measured in whole system total power drawn to complete a variety of cuda tasks, that card is most efficient around 225W or so… which is crazy considering they’re sold at 350W or more!

PragmaticPulp 4y ago

> Almost doubling the TDP for a 25%-30% frequency increase isn't doing most any good Having 25-30% faster compile times, faster video renders, higher frame rates, snappier responses is huge. I don’t understand why you’re suggesting it’s not doing anyone any good. Our CPUs don’t run at 100% all of the time. If my CPU takes 200W instead of 65W for the small fraction of the day that I’m doing something CPU-intensive, the difference is absolutely negligible. I’m going to use more total power when I cook my dinner, probably. If you are the kind of person willing to give up 1/4 of your performance for slightly lower power consumption under load, then go for those slower chips. You’re not the target market for the premium grade performance parts.

chaimanmeow 4y ago
You have some good points, *if* the OS and apps that you are using are designed with care and regard for energy efficiency. In my experience it's often not the case. Edge with its sleeping tabs function is a big improvement and example when app writers do care a bit about not wasting loads of energy. But it's really a very mixed bag. Many browsers do not. And there is plenty of nuissance javascript that will peg the CPU and RAM all day long. If you're a Steam user, you know that almost all games, when you idle them in the background, and even in pause mode, peg one or a few CPU threads as well as the GPU. The problem is greatly reduced for those editing their windows power profiles (or for linux users, cpufreq-set) to have their processors run at reduced frequencies. For those it might justify getting 105W X's over the 65W. Now the almost 30% peak perf gain that the X models can sustain are potentially a big advantage. Yet real life usage speedup isn't as big as one might expect from looking at benchmark multithread compute scores; compiling has a lot of waiting on IO. And the single thread differences between the mellow frequency non-X and the souped up X versions are not very big, percentage wise. So you might get 30% speedup for some cases, but probably more typical difference might closer to ~15%. iGPU throttling is an area where the 65W models would be disadvantaged at, sometimes significantly. So in some cases (workstation type usage), especially if running without a dedicated video card, the 105W choice might admittedly make good sense. 65W vs 105W bottom line: I guess it's a case of YMMV.