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>old CPUs that consume ~100W

Sandy Bridge consumes that much at full load, but that can also be said of current gen processors (which incidentally usually go even higher).

At idle or low load, Sandy Bridge is plenty economical just sipping power. These aren't Pentium 4s which guzzle power like it's draining Texas of its all its oil even at idle.

My Sandy Bridge i7 2700K is sipping 10W at idle/low load right now, and that's actually lower than my Alder Lake i7 12700K that's sipping 15W at idle/low load. At high loads they go up to 95W and 150W respectively, which still comes out in favor of Sandy Bridge.

>At idle or low load, Sandy Bridge is plenty economical just sipping power.

"Sipping power" is a bit of an overstatement. Sure, at 35W idle, they were very lower for the time but modern <10nm monolithic die CPUs are way more economically than the older 32nm, 22nm, and 14nm CPUs though. That can't be argued.

A 12th Gen quad core NUC CPU will use at full load what Sandy Bridge quad core uses at idle, while also getting better performance.

There's just no comparison.

Where do you get this number 35W from? My Ivy Bridge 3470 idles at 7 watt (cpu only). Most of energy is consumed by the monitor anyway (20-25 Watt) anyway, so the energy savings are minuscule.

>Where do you get this number 35W from?

A google search on benchmarks and tests.

I actually measured the whole system. With motherboard, HDD, SSD and RAM it idled at 30W. CPU took only 7w from all of that.

How did you measure CPU draw?

Reported by the motherboard's current sensor.

Is that accurate?

CPU and mobo sensors are accurate enough for casual measurements and conversations like this.

The numbers I cited earlier were reported by the CPU's package power sensors which were in turn read by LibreHardwareMonitor.

Well if you count expected power consumption of each component and limited efficiency of the power supply, plus reports of people idling their 3470 based machines at 12w (full system) yeah, good enough. I mean what is your point? The 35W idle for Ivy Bridge CPU only is a ridiculous claim, that should be retracted IMO.

(Not the same commenter) HWInfo64 can report your CPU power consumption. Some digital power supplies can also give power for specific parts, like corsair iCue compatible PSU's

Idle power consumption is hard to compare because peripherals, configuration and firmware have enormous sway.

However, painting with broad brushes, Sandy Bridge has modern power management and idles comparably to newer CPUs (a lot better than some modern ones even).

Yes, at full load a 12th gen NUC will be more efficient. But if you're just using the old system as a home server, most the time the CPU is idling and not consuming much more power than a new NUC.

Also an old system is likely in a case that accepts multiple drives. That NUC is not going to have space for my 3.5" storage drives. Yes I could invest in NVME SSD's, but the point of this is low cost and using parts I already have.

I have 10+ old 3.5" HDD's laying around, if one dies I can easily swap it out at zero cost to me and keep my home server going.

>That NUC is not going to have space for my 3.5" storage drives.

We were just comparing CPU power usage. We're going off-road here and splitting hairs trying to cater to the needs of every enthusiast who builds his custom home lab.

Nobody's telling you how you should build your NAS or home lab, but the point about big differences in CPU power consumption across >10 years of progress still stands.

I've got an Ivy Bridge quad core system in my closet that my UPS states is currently using ~15W of power with a few HDDs in it and an extra NIC as well. 35W idle CPU usage is thoroughly incorrect.

I disabled c states on my 13900K because it was chirping/squealing at low idle which irks me. Was hoping for that modern low tdp idle.

Chirping?

Coil whine, if I had to guess.

> there's a balance where you need to think how much of the environment and money would I be saving by keeping using very old hardware instead of throwing it away,

... maybe? Think global. Making CPUs uses an amazing amount of power in making the metallurgical silicon, refining to poly silicon, refining it again to semiconductor grade, refining it again, and then the whole slice polish lithography chain. All of that is still coal powered.

And the chemicals used, and the byproducts created in the chemical manufacture and use, and the amazing quantities of water that are used in the earlier steps of the chain.

Unless you're getting your electricity by burning rainforests, it seems better for the environment to avoid causing new chips to be made, by continuing to use old ones.

It's relatively safe to assume that a $200 CPU contains less than $200 worth of embodied energy. And while the energy used to manufacture the CPU will be cheaper than what a European pays at the outlet, it's not that much cheaper.

your reasoning assumes no subsidies

$200 is a gross upper limit. It's more likely that a $200 CPU contains $20 of embodied energy. It's highly unlikely that the energy is subsidized by >90%.

Your points are valid, but we also have to factor in the amount of electricity consumed by gen X chip vs gen X+1 chip to perform certain amount of computing during their lifetime.

Also don't forget the amount of energy required to deliver it to your house, and the fact that energy is probably more carbon-intensive than the energy powering your old CPU.

>Unless you're getting your electricity by burning rainforests, it seems better for the environment to avoid causing new chips to be made, by continuing to use old ones.

You're also paying for the extra electricity the old CPU uses out of your pocket, plus the extra time it takes to finish certain tasks, lowering your productivity loosing you money.

If you value energy efficiency and productivity, you can upgrade and flip the old CPU on the second hand market to someone for whom the energy efficiency and productivity gains are less important than using an old cheap CPU instead of buying a new expesnive one. Win-win.

The price of a new processor readily embodies the energy used to create it (by a significant margin, because of all the other stuff that needs to be paid for by the price of the processor)

It's a very safe bet that, assuming you do significant work with the processor, that a modern processor will more than make up for its inefficiency.

Environmental damage is mostly not included in the price of goods. Economics has a word, externality, to describe this.

Right, but we were talking about the energy embodied in manufacturing a processor. It should be obvious that the price of the processor includes the cost of the energy needed to manufacture it, and therefore there is a clear cap on how much extra energy a processor can consume before it would be obviously better to get a more modern and efficient processor.

Yeah it all depends from how much you actually use the machine, My old i7 gaming system runs maybe 7 hours a week on average. I drive barely 10k kilometers a year with my old ICE car. Upgrading to a new gaming PC and Tesla would make neither economic or environmental sense.

Yes, that's exactly why I emphasized "daily driver" like 3-4 times in my argument. If you hava a gas guzzling gaming PC that you use rarely because your daily driver is an M1 or ARM tablet, then that inefficient PC doesn't make a difference.

My point was only if these old PCs are daily driven on a daily basis as workhorse machines, then the lack of efficiency becomes an sensible issue.

the term daily driver says nothing about the overall distance. It only describes the frequency

> For example, a modern CPU encoding/decoding a video stream would use way less power thanks to its newer video decoder/encoder hardware IP blocks than a very old CPU going on full blast to SW decode/encode the video stream. The differences can be staggering.

Is that the case for Teams / Zoom & friends, which are what I'd expect to be the most common video decode/encode uses? I'm expecting my 11th gen i7 laptop to become airborne any day now, with the kind of noise it makes on Teams calls.

Anecdotally, my personal zen3u laptop does seem to unload video decoding to the GPU when watching movies, but it still gets fairly warm.

> If you don't care about energy efficiency or it's dirt cheap where you live then that's fine, but FWIW a modern 12th gen Intel Alder-Lake N100 NUC clone with quad E-cores[1] will smoke that

On what do you base this? I've never tried the N100 NUC, but some i5 12th gen with 2 P cores and I forget how many E-cores in a laptop. Compiling Rust, it was comparable to my older gen laptop with the 11th gen i7. Now this is an "U" part in an ultra book, but it's barely faster than a 2013 MBP with an i7, which, if I'm not mistaken, is a 3rd gen core "H" part.

My i7-3770 system I mentioned in another post here pulls 100 watts from the wall with p95 and furmark running everything at 100%. When actually gaming it's usually under 90 watts....

My old fx6300 system though pulled +250 watts just existing lol.

When I was running the stack of SFF business machines I was using vastly more power to cool the room than I was to power the machines.

At $0.12/kWh 1W 24/7/365 costs $1/year. Assuming you don't use sleep mode and/or wake on LAN dropping down from 50W to 10W will save $40/year.

On the environmental virtue side electronics have embodied energy usage that can surpass the lifetime electrical consumption especially if the devices are not always on.

If you read my comment again, I specifically singles out the EU energy proces because I knew North America has much cheaper electricity which is why I specified if you have cheap energy then it probably won't matter for you.

And Europeans are definitely feeling the CoL increase.

Right. It seems paradoxical to save money by spending money on new machines. Versus low hanging fruit like turning off or sleeping unused nodes or taking a hard look at your computing footprint and downsizing.

It's not paradoxical to buy a CPU that's 5x more efficient.

Whether it is a net win for energy consumption entirely what you're using it for and how the entire power profile of the system looks, not just the CPU and not just at full power.

If it uses as much or more power when busy and you're just using it to push more frames in a video game, you're probably not going to singlehandedly bring about the next ice age. Same if the low utilization system power is similar and you spend most of the time messing around on the internet or editing code occasionally punctuated by a compile job, even if that does run faster.

Hardware video encoding is a poor example as it is typically lower quality than software for a given bitrate

Maybe, but you get the point on energy efficiency though , no need to go into semantics of encoder quality as that was not the point, just an example off the top of my head that resonated with my anecdotes when i upgraded from a Core 2 Duo.

Even with SW only workloads, just look at the geekbench scores I posted.

If a 2W smartphone SoC can offer over 2x the performance of a 95W chip, then it's bit outdated and energy inefficient and maybe time to upgrade to something better and more energy efficient, unless you're tryin to compete in the "who has the most gas-guzzling terminal/youtube machine" competition.

Something people often overlook when comparing power usage of PC components, is that you often have to multiply the watt difference by 3x (or 4x) when you factor in cooling (air conditioning I mean, in regards to how to dissipate that heat generation, in your home).

I.e. PC-A might consume 100 watts more than PC-B, but the real efficiency when it comes to you our monthly electric bill is more like 300 to 500 W (in my experience, in a hot area of the country). Those 100 W of heat have to be removed from your home environment to keep whatever Ambient temperature you find comfortable.

Edit-it of course, works in the opposite direction in terms of your heating bill in the cold months of the year (but without the 3X multiplier)

In most of Europe this isn't very applicable as most of Europe doesn't have any kind of active cooling in houses like A/C.

>In most of Europe this isn't very applicable

You're mistaken. In most of Europe thermodynamics are still very much applicable, lack of AC doesn't mean your hot computer doesn't make your room warmer anymore, so extra heat from an old inefficient computer still ends up in your house, raising your ambient temperature and making you uncomfortable (in the summer) regardless if you have AC or not.

Lack of AC doesn't make the "hot computer making my room warm" problem go away, it just makes it a better case for investing in thermally efficient electronics because you have no AC to vent it out with.

But it doesn't multiply the watt consumption of a home without AC, which was your original point.

Yes, but we tend to focus on passive cooling rather than active cooling - your comment was all about active cooling and the extra costs thereof, and passive cooling techniques do not imply an extra power cost.

But yes - modern lower power hardware (Apple Silicon, lower power AMD Zen, etc) can be drastically faster than older hardware, at significantly lower power - and massively lower total power consumption for work done.

You can get wins here by making sure even modern hardware is running in the more power efficient part it's perf/watt curve - for example, ECO mode on modern AMD hardware (105W+ to 65W, for instance), reducing the board power limit on GPUs when doing compute (~420W to 225W, for most efficient on my 3090!), etc. You lose remarkably little performance by doing so.

Northern Europe maybe. But A/C is pretty common in the Mediterranean. The only difference is that central A/C is correctly seem as something that makes sense in comercial spaces, not homes.

At homes what is more common are ductless split systems, combined with an architecture where you have windows that can be opened when the weather is not that hot.

It is completely idiotic to cool a whole McMansion when the 3 or 4 people inside are occupying no more than 30% of the space most of the time.

> is that you often have to multiply the watt difference by 3x (or 4x) when you factor in cooling (air conditioning I mean, in regards to how to dissipate that heat generation, in your home).

Where are you getting these numbers from? Typical central air CoP (Coefficient of Performance) even when it's > 100 F outside is at least 2, typically 3-5. Assuming based on current outdoor temp the CoP is 3, it'll remove 100 W of heat with 33 W of energy. So instead of 100 W -> 300-500 W you're looking at 100 W -> 133 W total.

> a 2W smartphone SoC can offer over 2x the performance of a 95W chip

2x performance in some very specific and narrow benchmark tasks.

Exactly. If you have the latest and greatest mobile phone and 8GB (or 12GB) of LPDDR5 on a Snapdragon 8 Gen 2 soc you still only have 8.5 Gbps memory bandwith (max, less in actual phones running it at slower speeds). That's 1 GB/s. An ivy bridge i5 3570k has a memory bandwidth of 25 GB/s. Even an ancient Core 2 Duo has 5GB/s memory bandwidth at stock speeds. Phones are very bad at computing tasks outside of "watching video" "buying things online" and the like.

Something is really off with your calculations. High-end Snapdragon chips are running with at least 64-bit busses, combined with the clock speed advantages LPDDR5 should put it well ahead of any 128-bit DDR3 system. At least 50GB/s.

The real reason phones are bad at computing tasks is they throttle when put under any sustained load.

I'm seeing a lot of specs for that chip listing 64Gbit/s and some showing GB/s. I'd love to see some confirmation of actual performance.

Depending on clock speed of memory. For LPDDR5-6400 which is pretty common.

3200000000(clock) x 2(DDR) x 2(16-bit channel width) x 4(channels) = 51200000000 bytes/sec or 51.2 GBytes/sec

16 bits is where you added data width here, so that would be 52 gigabits a second, no? To go to bytes wouldn't we need to divide by 8?

And I imagine this commenter talking about 8GB RAM, they're assuming not all 4 channels are populated. So one could imagine two channels being populated, 25.6 Gbit/sec, divide by 8 to get bytes, that's then only 3.2GB/s?

I multiplied by 2 instead of 16. That's what makes it bytes.

Ah ok I see what you did there, thanks for the explanation.

The new crap is more user-hostile and loses backwards compatibility. I'm not enticed by efficiency or environmental virtue signaling.

As the saying in the car enthusiast community goes: "It's not about the miles per gallon, it's the smiles per gallon."

In what way is it user hostile?

Backwards compatibility to what, MS-DOS? People usually complain about forward compatibility regarding TPM, never had any issues with backwards compatibility on the last chips.

How is more money in your pocket virtue signaling?

heh… next to this tower PC is a rack loaded with networking gear and 2x maxed out R720 machines with redundant 1100w power supplies. My electrical bill is around $100/mo.