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by jeffbee 595 days ago
If you are getting 125W at the wall on a PC at idle, your machine or operating system is extremely broken, or you are running atmosphere physics simulations all the time. The SoC on my Intel box typically drew < 1W as measured by RAPL. The 9950X draws about 18W measured the same way. Because of platform overhead the difference in terms of ratio is not that large but the Ryzen system is drawing about 40W at the wall when it's just sitting there.
2 comments
zokier 595 days ago
Discrete gpu can easily add 20-40w of idle power draw, so that's something to keep in mind. I believe that 60ish watts is pretty typical idle consumption for desktop system, Ryzens typically having 10w higher idle draw than Intel. Some random reviews with whole system idle measurements:

https://hothardware.com/reviews/amd-ryzen-7-9800x3d-processo...

https://www.techpowerup.com/review/amd-ryzen-7-9800x3d/23.ht...

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jeffbee 594 days ago
Those comparisons are using a water cooling rig which already blows out the idle power budget. 60W is in no way typical of PC idle power. Your basic Intel PC draws no more power than a laptop, low single digits of watts at the load, low tens of watts at the wall. My NUC12, which is no slouch, draws <5W at the wall when the display is off and when using Wi-Fi instead of Ethernet.
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mdre 594 days ago
Hmm. I’m using an AIO cooler, a 3090 and a 1600W platinum psu - might be a bit inefficient. I remember unplugging the PSU and 3090 and plugging in a 650W gold PSU — the system drew 70W IIRC. That’s a wild difference still!
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jeffbee 594 days ago
Yeah, oversized power supplies are also responsible for high idle power. "Gold" etc ratings are for their efficiency at 50%-100% rated power, not how well they scale down to zero, unfortunately. I have never owned a real GPU, I use the IGP or a fanless Quadro, so I don't have firsthand experience with how that impacts idle power.
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zokier 594 days ago
Gold rating is down to 20%, Titanium is to 10% https://en.wikipedia.org/wiki/80_Plus#Efficiency_level_certi...
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ac29 594 days ago
Platinum is 90% efficient at 20%, but OP is using a 1600W power supply, so that 20% is 320W. Any load below that is going to be less efficient.
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