PC desktop typical power consumption

[chagzuki]

I've not owned one for a very long time, and I'm assuming power management is much better now than when I did. What kind of power usage should one expect from e.g. a tower with a Ryzen 7 5800x with low spec graphics card, ssd, running Windows, idle and under load?

[chk071]

I've not owned one for a very long time, and I'm assuming power management is much better now than when I did.

Well, it is, but, simultaneously, performance has gone up.

Are you a gamer and need a good graphics card? If you don't, power consumption will be signinificantly lower.

The Ryzen 7 5800X has a maximum power consumption of 218 Watt, by the way. Of course, that will only happen very, very rarely. It's still a lot, and, power consumption on lower loads will be pretty high as well. Dunno what it takes when it idles, but, I would estimate 60 to 80 W.

[chagzuki]

Are you a gamer and need a good graphics card? If you don't, power consumption will be signinificantly lower.

The Ryzen 7 5800X has a maximum power consumption of 218 Watt, by the way. Of course, that will only happen very, very rarely.

No, no gaming here. What is idle-ish likely to look like?

[chk071]

Should be about 60 to 80 W. https://www.google.com/search?q=Ryzen+7 ... e&ie=UTF-8

[Kr3eM]

If anyone fancy some nerding...

Power consumption of Ryzen 5000 series CPUs
https://hattedsquirrel.net/2020/12/powe ... ries-cpus/

For my very minimal Ryzen 9 5900X machine with dedicated GPU I could get it down to these numbers:

27W in complete idle, monitor off
~53W for rapid mouse curser movement and no other load
57W at playing a YouTube video

That already includes 8W (idle) / 10W (otherwise) for a RTX1650 Super grapcis card, since the CPU doesn’t include an iGPU. You might get lower numbers if you find a graphics card with lower idle consumption.

[agharta]

The choice of power supply can make a big difference at idle.
A good idle wattage for a system like that is 35 - 45 Watts.

[Markus Krause]

That's what I measured on my side:

My AMD Ryzen Desktop needs around 70-150W - It depends on the CPU load. It's a high-end audio machine with all power-saving functions disabled.

The screens need around 50-150W per instance. I noticed that my gaming screens with support for high framerates need twice as much than conventional ones.

The Laptop is around 30W.

Yamaha HS80 Speakers (active) need around 35W.

[chagzuki]

Lots of reference points, cheers all.

Are there any particular specs to pay attention to when choosing a power supply, in terms of efficiency?

[Pictus]

Many...
Check the reviews:

https://www.techpowerup.com/review/?cat ... order=date

https://www.tomshardware.com/topics/power-supplies

[cel4145]

No one suggested using a PSU calculator?

https://outervision.com/power-supply-calculator

[Markus Krause]

Stay away from cheap power supplies. They can cause an instable system and even can do damage to your hardware. You can get random crashes. Cheap capacitors can run more quickly out of the specification and cause weird side-effects.
They even have a negative impact on the sound (!) because the DC power supply additional contains garbage currencies. Soundcards do not like this.

[newjunkcity]

Are there any particular specs to pay attention to when choosing a power supply, in terms of efficiency?

Stay away from cheap power supplies.

Apart from the above (stay away from cheap ones, it's not worth it long-term), PSUs follow a power efficiency rating system, with 'Gold', 'Platinum', and 'Titanium' specced PSUs having the best power efficiency:
80 Plus

Note also that most PSUs are the most efficient at around 50% utilisation:


Image from a Seasonic PSU product page


My current workstation pulls around 550W when I'm thrashing both the GPU and CPU, and as that's surprisingly often, I went for a 850W PSU specifically to obtain better efficiency at load than a 650W PSU would offer (even though the 650W PSU would run the system perfectly fine). This probably results in worse idle efficiency, but seeing as the system goes to sleep after 20 mins without activity, and also that we're talking about a worse efficiency %-age at a very low power draw to begin with, this doesn't bother me at all. (i.e. 2% difference at idle (on 50W) is far less than 2% difference at load (on 550W).)

If you don't mind me asking, is a there a specific reason you're looking to economise over a few watts here and there? In most places, it won't make all that much difference to the electricity bill - the best thing you can do is turn off the workstation when not using it; and if you're looking for an always on (24/7) server, then desktop components and OS are generally a bad choice anyway. Perhaps you have heat output requirements, or are running a mobile rig off of batteries?

[2DaT]

Stay away from cheap power supplies. They can cause an instable system and even can do damage to your hardware. You can get random crashes. Cheap capacitors can run more quickly out of the specification and cause weird side-effects.
They even have a negative impact on the sound (!) because the DC power supply additional contains garbage currencies. Soundcards do not like this.

Depends on how cheap.

I always used budget PSUs, never had any problem. But these were like 50$, not 20$. If you buy 20$ noname chinise PSU chances are it's not good.

I also think today PSUs are better than they were in early 2000s. In 2000s cheap PSUs were indeed horrible.

Expensive PSU is justified if:

1. You need a quiet system. Expensive PSUs generate less heat and have way better fans.
2. The rest of the system is expensive.

Buying 150$ PSU for 700$ system is not smart. And vice versa buying 50$ PSU for 2000$ system is not smart either.

As for the soundcard, mostly they have their own power filtering. Shoudn't matter that much. Where PSU can matter is EMI produced by PSU, that can interfere with sensitive equipment nearby. But spending a lot of money doesn't guarantee low EMI levels, sometimes quite the contrary.

[chk071]

Apart from the above (stay away from cheap ones, it's not worth it long-term), PSUs follow a power efficiency rating system, with 'Gold', 'Platinum', and 'Titanium' specced PSUs having the best power efficiency:

*checks his PSU's specs*

Platinum, yay!

[PAK]

If you don't mind me asking, is a there a specific reason you're looking to economise over a few watts here and there? In most places, it won't make all that much difference to the electricity bill

Hehehe. I already knew the answer without checking. They're in the UK.

The UK has just presided over a 54.3% increase in electricity costs. Presently it's 28.34p, or US $0.35c per kWh (the price is "capped" by the government). This is likely to rise a further 20% within 5 months. For comparison, according to EIA.gov, the US will see a 3.9% increase in 2022, for a national average of 14.26c per kWh. So the UK, a nation which has the resources to be self-sufficient in energy if it so chooses, will instead import it (muh fake carbon zero targets) and thus pay approximately triple what the USA does. The price doesn't include UK standing charges either.

For a sizeable chunk of the UK population such costs are now sufficiently prohibitive that, if you plan to own a computer for several years and run it for long periods or 24/7, power usage is now a major cost factor which must be included. You will own nothing and be happy.

the best thing you can do is turn off the workstation when not using it; and if you're looking for an always on (24/7) server, then desktop components and OS are generally a bad choice anyway.

I suppose, but people usually want general purpose machines they can do several things with. Unless a big part of what you do is PC gaming an M1 Mac Mini is hard to beat, for performance Vs power usage, right now..