3 ms·

Also Intel CPUs have much lower consumption while idling, right? As much as I like AMD, I find this a significant advantage for a workstation / small server.

by nextos 3y ago

adrian_b 3y ago
It is true that the desktop Intel CPUs have lower idle consumption, usually by 10 to 15 W, than the desktop AMD CPUs. On the other hand, for any given performance at full load, the AMD CPUs have a much lower power consumption, as low as two thirds. Which is preferable depends on the application. For a personal computer, idle power consumption may be the most important. For a server, the power consumption when used is normally more important. I have several servers in my home, which are used intermittently. Their idle power consumption does not matter much, because whenever they are not used they are shut down. Wake-on-Ethernet is enabled on them, and whenever I use them Ethernet magic packets wake them immediately. The Intel E-cores are quite good for mostly integer workloads, like code compilation, or for file servers or Web servers, so for such tasks the Intel CPUs are adequate (but ECC-supporting MBs for them are quite expensive). On the other hand their floating-point performance is quite poor (and the P-cores are few and intentionally crippled), so for such workloads AMD Zen 4 is much better, especially for running non-legacy programs, which have been updated and optimized for the modern ISAs.
- nextos 3y ago
  I thought the idle consumption difference was much larger than 15 W. Do you have any links to reliable benchmarks?
  - adrian_b 3y ago
    I do not remember now, but there have been a large number published. The wall plug idle power consumption that I have seen published for recent Intel-based desktops was usually around 30 to 35 W, about the same as of the older Kaby Lake or Coffee Lake based computers that I have. The wall plug idle power consumption of Ryzen-based desktops, both as published and also valid for a couple of Ryzens that I use, is about 40 W to 50 W. (The idle Ryzen cores consume a negligible total power of less than 1 W, but the I/O die consumes 20 to 30 W, even when idle.) The desktops that have GPU cards have higher idle power consumptions than these. The (well-designed) small computers like Intel NUC or similar, which use mobile CPUs, have a wall plug idle power consumption of 5 to 10 W, regardless whether they use Intel Core or AMD Ryzen. When the idle power consumption is a concern, the real solution is to use a small computer with a volume of less than 1 liter and a mobile CPU as the workstation (there are now models with Ryzen 9 7940HS or Intel Core i9-13900H, which are more powerful than most big desktops from just a few years ago), and to use big desktop computers only as servers that sleep when they are not used.

Also Intel CPUs have much lower consumption while idling, right? As much as I like AMD, I find this a significant advantage for a workstation / small server.

by nextos 3y ago

Also Intel CPUs have much lower consumption while idling, right? As much as I like AMD, I find this a significant advantage for a workstation / small server.

adrian_b 3y ago

It is true that the desktop Intel CPUs have lower idle consumption, usually by 10 to 15 W, than the desktop AMD CPUs. On the other hand, for any given performance at full load, the AMD CPUs have a much lower power consumption, as low as two thirds. Which is preferable depends on the application. For a personal computer, idle power consumption may be the most important. For a server, the power consumption when used is normally more important. I have several servers in my home, which are used intermittently. Their idle power consumption does not matter much, because whenever they are not used they are shut down. Wake-on-Ethernet is enabled on them, and whenever I use them Ethernet magic packets wake them immediately. The Intel E-cores are quite good for mostly integer workloads, like code compilation, or for file servers or Web servers, so for such tasks the Intel CPUs are adequate (but ECC-supporting MBs for them are quite expensive). On the other hand their floating-point performance is quite poor (and the P-cores are few and intentionally crippled), so for such workloads AMD Zen 4 is much better, especially for running non-legacy programs, which have been updated and optimized for the modern ISAs.

nextos 3y ago
I thought the idle consumption difference was much larger than 15 W. Do you have any links to reliable benchmarks?
- adrian_b 3y ago
  I do not remember now, but there have been a large number published. The wall plug idle power consumption that I have seen published for recent Intel-based desktops was usually around 30 to 35 W, about the same as of the older Kaby Lake or Coffee Lake based computers that I have. The wall plug idle power consumption of Ryzen-based desktops, both as published and also valid for a couple of Ryzens that I use, is about 40 W to 50 W. (The idle Ryzen cores consume a negligible total power of less than 1 W, but the I/O die consumes 20 to 30 W, even when idle.) The desktops that have GPU cards have higher idle power consumptions than these. The (well-designed) small computers like Intel NUC or similar, which use mobile CPUs, have a wall plug idle power consumption of 5 to 10 W, regardless whether they use Intel Core or AMD Ryzen. When the idle power consumption is a concern, the real solution is to use a small computer with a volume of less than 1 liter and a mobile CPU as the workstation (there are now models with Ryzen 9 7940HS or Intel Core i9-13900H, which are more powerful than most big desktops from just a few years ago), and to use big desktop computers only as servers that sleep when they are not used.