3 ms·

Also, 280w comes out to be about $58 a month in electricity for Bay Area pricing (29c/kWh). Collocation will probably be cheaper for some folks.

m0zg 7y ago
That's only if you use all cores 24x7 and all ALUs within those cores (vectorized workloads), which is very unlikely unless you're doing straight up linear algebra on the CPU. In CA there's also the issue of not having electricity in the first place sometimes though. So power _consumption_ seems kind of secondary.
- Dylan16807 7y ago
  > That's only if you use all cores 24x7 and all ALUs within those cores These chips don't run at a fixed frequency. They dynamically adjust based on thermal limits and power limits. You only have to burden most of the cores/ALUs to hit maximum power. Any load above that threshold uses the same amount of power, as frequencies nudge down to compensate.
  - simooooo 7y ago
    That doesn’t sound right
    - Dylan16807 7y ago
      Why doesn't it sound right? Just look at the chart in the article: https://images.anandtech.com/doci/15044/3970X%20Power%20Graph.png https://images.anandtech.com/doci/15044/3970X%20Power%20Grap... The power limit is configured in the BIOS, and can be disabled, but with these massive chips they default to throttling down and capping power consumption so that you aren't forced to go crazy with the cooling system (and motherboard and PSU capacity).
  - m0zg 7y ago
    According to the linked Anandtech article, the maximum TDP is reached at ~22 cores fully slammed, yes. But it doesn't drop off much after that. But that's splitting hairs.
Dylan16807 7y ago
But to be clear, California is a strong outlier. The average price in the US is 12 cents.
hajile 7y ago
AMD is getting almost 30% better performance at 287 watts than Intel at 380 watts (Intel W-3175X in the review). If you're actually using all 32 cores all the time, you're saving TONS of money overall. Not only are you doing 30% more work, but at 25% less power. Even if you left it on 24/7, it would take you a year and a half to make up the difference in price between the $2000 AMD and the $3000 Intel. If we assume both chips have identical performance, the Intel would cost $4350 to run over 5 years vs $3480 for the AMD (assuming 24/7 at all cores). The total cost of ownership for that Intel chip over 5 years seems to be around 2x that of the AMD chip. I'd note we've been talking about 32 cores 24/7. If you're using 4 cores and 8 threads, you will be using half the power (about 140 watts). If your system is idling, it's using a bit less than 50 watts. Let's say you leave your system on 24/7. You work 8 hours, play 4 hours (4 cores, 8 threads constantly running), and it idles the other 12 hours. We'll assume that you somehow max all cores for your entire workday and max 4 cores during play. You'd be well under half that price per month. Change all-out time to a more reasonable, but still strenuous 4 hours with 8 moderate hours and shutting off your computer at night will get you down to less than $20 per month.

m0zg 7y ago

That's only if you use all cores 24x7 and all ALUs within those cores (vectorized workloads), which is very unlikely unless you're doing straight up linear algebra on the CPU. In CA there's also the issue of not having electricity in the first place sometimes though. So power _consumption_ seems kind of secondary.

Dylan16807 7y ago
> That's only if you use all cores 24x7 and all ALUs within those cores These chips don't run at a fixed frequency. They dynamically adjust based on thermal limits and power limits. You only have to burden most of the cores/ALUs to hit maximum power. Any load above that threshold uses the same amount of power, as frequencies nudge down to compensate.
- simooooo 7y ago
  That doesn’t sound right
  - Dylan16807 7y ago
    Why doesn't it sound right? Just look at the chart in the article: https://images.anandtech.com/doci/15044/3970X%20Power%20Graph.png https://images.anandtech.com/doci/15044/3970X%20Power%20Grap... The power limit is configured in the BIOS, and can be disabled, but with these massive chips they default to throttling down and capping power consumption so that you aren't forced to go crazy with the cooling system (and motherboard and PSU capacity).
- m0zg 7y ago
  According to the linked Anandtech article, the maximum TDP is reached at ~22 cores fully slammed, yes. But it doesn't drop off much after that. But that's splitting hairs.

Dylan16807 7y ago

But to be clear, California is a strong outlier. The average price in the US is 12 cents.

hajile 7y ago

AMD is getting almost 30% better performance at 287 watts than Intel at 380 watts (Intel W-3175X in the review). If you're actually using all 32 cores all the time, you're saving TONS of money overall. Not only are you doing 30% more work, but at 25% less power. Even if you left it on 24/7, it would take you a year and a half to make up the difference in price between the $2000 AMD and the $3000 Intel. If we assume both chips have identical performance, the Intel would cost $4350 to run over 5 years vs $3480 for the AMD (assuming 24/7 at all cores). The total cost of ownership for that Intel chip over 5 years seems to be around 2x that of the AMD chip. I'd note we've been talking about 32 cores 24/7. If you're using 4 cores and 8 threads, you will be using half the power (about 140 watts). If your system is idling, it's using a bit less than 50 watts. Let's say you leave your system on 24/7. You work 8 hours, play 4 hours (4 cores, 8 threads constantly running), and it idles the other 12 hours. We'll assume that you somehow max all cores for your entire workday and max 4 cores during play. You'd be well under half that price per month. Change all-out time to a more reasonable, but still strenuous 4 hours with 8 moderate hours and shutting off your computer at night will get you down to less than $20 per month.