3 ms·

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.

by jeswin 4y ago

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".
- sudosysgen 4y ago
  Well not really. If you are using your CPU near 100% 24/7, then getting a CPU which is 50% faster means that you're going to be using around 50% fewer computers, right? And also, which CPUs are you talking about which use 40W under load at anywhere near this kind of performance?
- chaimanmeow 4y ago
  Except in heating season about 35% of that expense is recovered, as all these appliances contribute to heating the home (at the same efficiency/cost as resistor heaters).
pedrocr 4y ago
The difference is much starker in this generation in particular. It's 60% to 160% more power to get a 5 to 10% benefit. Intel was left behind by AMD and started competing by cranking the power up. In this generation AMD responded in kind and we are just too far off in the efficiency curve. Even the X parts are best ran in their ECO modes.

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.

by 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".
sudosysgen 4y ago
Well not really. If you are using your CPU near 100% 24/7, then getting a CPU which is 50% faster means that you're going to be using around 50% fewer computers, right? And also, which CPUs are you talking about which use 40W under load at anywhere near this kind of performance?
chaimanmeow 4y ago
Except in heating season about 35% of that expense is recovered, as all these appliances contribute to heating the home (at the same efficiency/cost as resistor heaters).

pedrocr 4y ago

The difference is much starker in this generation in particular. It's 60% to 160% more power to get a 5 to 10% benefit. Intel was left behind by AMD and started competing by cranking the power up. In this generation AMD responded in kind and we are just too far off in the efficiency curve. Even the X parts are best ran in their ECO modes.