6 ms·

There sorta is a cap in place given that most residential circuits in the US are 15 or 20 amps. We're already not far off of that being a serious concern even o

by gh02t 4y ago

There sorta is a cap in place given that most residential circuits in the US are 15 or 20 amps. We're already not far off of that being a serious concern even on non-crazy builds. Edit: ok maybe crazy builds but still it's not that far fetched on current trajectories.

kenhwang 4y ago
I don't know if I'd call 1800W (residential circuit limit) builds "non-crazy". Even half that power is rare to see since that's pretty much two top of the line consumer graphics cards paired to a top of the line enterprise CPU.
- jquery 4y ago
  Two 3090s plus a 64 core Threadripper pro will get you beyond 1000 watts alone. Don’t forget power for the 512gb of ram (200 watts), the motherboard, the fans and hard drives and accessories and gamer lights (well, gamer lights aren’t necessary). That’s definitely a crazy build though.
  - jsjohnst 4y ago
    > Two 3090s plus a 64 core Threadripper pro will get you beyond 1000 watts alone. Don’t forget power for the 512gb of ram (200 watts), the motherboard, the fans and hard drives and accessories Yes, PEAK instantaneous wattage could easily be well over 1kW for a crazy rig like that, but unless you are specifically torture testing the rig over a long duration, it simply isn’t accurate that you are drawing anywhere near the max continuously under gaming conditions. > Two 3090s plus a 64 core Threadripper pro will get you beyond 1000 watts alone 3090s are 320/350W each and 64 core Threadripper Pro has a TDP of 280W, just as an FYI.
jsjohnst 4y ago
> We're already not far off of that being a serious concern even on non-crazy builds. Show me an example of a “non-crazy” build that’s over 1,200W, let alone over 1,500W. I’m genuinely curious.
- gh02t 4y ago
  I said near, we still have some breathing room. But as noted elsewhere, 15 A is a max for short periods, the practical limit for continuous use is more like 1200-1400 W which definitely seems like it might be plausible soon. Plus other things on the circuit. Fancy ultra bright HDR monitors use a decent chunk of power, and anything else.
  - jsjohnst 4y ago
    > But as noted elsewhere, 15 A is a max for short periods, the practical limit for continuous use is more like 1200-1400 W which definitely seems like it might be plausible soon. Per NEC in the US, the wire used in a circuit has to be rated to handle a current draw of up to 80% continuously at the specified temperature max for the type of installation. 80% of 15 is 12, the average home in the US has split phase incoming power with a nominal voltage of 120V (1440W) with many as high as 125V (1500W). Note that is current draw over long periods of time, which a gaming rig under heavy gaming won’t usually do. Maybe a mining rig back in the day would, but otherwise it’s just not true you’re continuously drawing anywhere near 1,000+ watts on anything but the most crazy setups. > I said near, we still have some breathing room. No, you made a wild ass conjecture not based in fact and when gently questioned on it, you shifted goal posts and made up more conjecture.
  - Sohcahtoa82 4y ago
    1200 W, even for a short period of time, is crazy for a desktop computer. I have an i9-9900K and an RTX 3080. My computer is also plugged into a Kill-a-watt to measure its power usage. I ran Prime95's CPU torture test using the max power option while also crypto-mining on the GPU. I peaked at 650 watts for a couple seconds until the CPU began thermal throttling. If I can't hit 700 watts while trying to use as much energy as possible, I can't imagine what monster system would even touch 1000 watts, assuming we're still talking consumer-grade.
    - gh02t 4y ago
      Counting my monitors and the small network switch on my desk, I can hit around 750-800 watts sustained with a 5950X and a 3090 running compute intensive workloads as measured at the wall by a power meter. So yeah, there's plenty of head space but I have also hit circuit breaker issues recently on a proper (non consumer) workstation so the limit is fresh in my mind.
MBCook 4y ago
So 15 A x 120 V is 1800 W. The problem is even in a dedicated circuit you can’t use that continuously, it’s considered dangerous. For continuous draw you’re limited to 80% of the line’s rating (in the US). People who have looked into EV charging have certainly run into this fact. So the computer (and sound/monitor/etc) have to stay under ~1400 watts if it’s on a dedicated circuit. 1/3rd of that for just the GPU I’d pretty crazy. I honestly wouldn’t have thought GPUs could get this high. Also, I remember my computers being hot in a small room long ago. A lot of the space heaters on Amazon are rated either 750 or 1500 W. I don’t think I wanna be near a computer that hot.
- midoridensha 4y ago
  Don't forget the PSU isn't perfectly efficient; it's usually between 80 and 90 percent. So for safety, about 1100W (for the total of the DC power draws of the components fed by the PSU) is really the maximum for continuous draw, and as you pointed out, there's also monitors, sound, etc. A typical monitor now is probably 50W or so (which is actually really good compared to the CRT behemoths of yesteryear).

by gh02t 4y ago

kenhwang 4y ago

I don't know if I'd call 1800W (residential circuit limit) builds "non-crazy". Even half that power is rare to see since that's pretty much two top of the line consumer graphics cards paired to a top of the line enterprise CPU.

jquery 4y ago
Two 3090s plus a 64 core Threadripper pro will get you beyond 1000 watts alone. Don’t forget power for the 512gb of ram (200 watts), the motherboard, the fans and hard drives and accessories and gamer lights (well, gamer lights aren’t necessary). That’s definitely a crazy build though.
- jsjohnst 4y ago
  > Two 3090s plus a 64 core Threadripper pro will get you beyond 1000 watts alone. Don’t forget power for the 512gb of ram (200 watts), the motherboard, the fans and hard drives and accessories Yes, PEAK instantaneous wattage could easily be well over 1kW for a crazy rig like that, but unless you are specifically torture testing the rig over a long duration, it simply isn’t accurate that you are drawing anywhere near the max continuously under gaming conditions. > Two 3090s plus a 64 core Threadripper pro will get you beyond 1000 watts alone 3090s are 320/350W each and 64 core Threadripper Pro has a TDP of 280W, just as an FYI.

jsjohnst 4y ago

> We're already not far off of that being a serious concern even on non-crazy builds. Show me an example of a “non-crazy” build that’s over 1,200W, let alone over 1,500W. I’m genuinely curious.

gh02t 4y ago
I said near, we still have some breathing room. But as noted elsewhere, 15 A is a max for short periods, the practical limit for continuous use is more like 1200-1400 W which definitely seems like it might be plausible soon. Plus other things on the circuit. Fancy ultra bright HDR monitors use a decent chunk of power, and anything else.
- jsjohnst 4y ago
  > But as noted elsewhere, 15 A is a max for short periods, the practical limit for continuous use is more like 1200-1400 W which definitely seems like it might be plausible soon. Per NEC in the US, the wire used in a circuit has to be rated to handle a current draw of up to 80% continuously at the specified temperature max for the type of installation. 80% of 15 is 12, the average home in the US has split phase incoming power with a nominal voltage of 120V (1440W) with many as high as 125V (1500W). Note that is current draw over long periods of time, which a gaming rig under heavy gaming won’t usually do. Maybe a mining rig back in the day would, but otherwise it’s just not true you’re continuously drawing anywhere near 1,000+ watts on anything but the most crazy setups. > I said near, we still have some breathing room. No, you made a wild ass conjecture not based in fact and when gently questioned on it, you shifted goal posts and made up more conjecture.
- Sohcahtoa82 4y ago
  1200 W, even for a short period of time, is crazy for a desktop computer. I have an i9-9900K and an RTX 3080. My computer is also plugged into a Kill-a-watt to measure its power usage. I ran Prime95's CPU torture test using the max power option while also crypto-mining on the GPU. I peaked at 650 watts for a couple seconds until the CPU began thermal throttling. If I can't hit 700 watts while trying to use as much energy as possible, I can't imagine what monster system would even touch 1000 watts, assuming we're still talking consumer-grade.
  - gh02t 4y ago
    Counting my monitors and the small network switch on my desk, I can hit around 750-800 watts sustained with a 5950X and a 3090 running compute intensive workloads as measured at the wall by a power meter. So yeah, there's plenty of head space but I have also hit circuit breaker issues recently on a proper (non consumer) workstation so the limit is fresh in my mind.

MBCook 4y ago

So 15 A x 120 V is 1800 W. The problem is even in a dedicated circuit you can’t use that continuously, it’s considered dangerous. For continuous draw you’re limited to 80% of the line’s rating (in the US). People who have looked into EV charging have certainly run into this fact. So the computer (and sound/monitor/etc) have to stay under ~1400 watts if it’s on a dedicated circuit. 1/3rd of that for just the GPU I’d pretty crazy. I honestly wouldn’t have thought GPUs could get this high. Also, I remember my computers being hot in a small room long ago. A lot of the space heaters on Amazon are rated either 750 or 1500 W. I don’t think I wanna be near a computer that hot.

midoridensha 4y ago
Don't forget the PSU isn't perfectly efficient; it's usually between 80 and 90 percent. So for safety, about 1100W (for the total of the DC power draws of the components fed by the PSU) is really the maximum for continuous draw, and as you pointed out, there's also monitors, sound, etc. A typical monitor now is probably 50W or so (which is actually really good compared to the CRT behemoths of yesteryear).