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Limiting powerconsumption in Desktop builds?

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Hi,

When looking at power consumtiopn charts for newer CPU's in Desktop computers such as I7 / I9 and Ryzen 3000
I'm surprised just how much power they consume these days even at IDLE (all the cores and threads). And Intels processers seem to be way over their promised TDP:
It's nice to have a powereffecient laptop (it feels like a waste to use a powerhungry Desktop for browsing the web and writing) for most of the daily tasks, but of course if you need a desktop for
heavy video editing or gaming you would need to build a Good desktop. So my question is this
Which CPU would you go for today if you were to build a desktop that colud do medium photo editing / 4K video editing: Ryzen or intel? Which generation and model?
Are there safe methods to limit the TDP or power draw? Are there smart ways to regulate GPU and CPU power draw these days fx at idle?

134347


Link to power consumption thread
wccftech.com

Intel Core i9-9900K 8 Core and 16 Thread 5.0 GHz CPU Review Ft. Z390 AORUS Master Motherboard

Intel has released their 9th Generation Core family and today, I'll be taking a lookg at their Core i9-9900K CPU onthe AORUS Z390 Master.
wccftech.com wccftech.com
 
Most, if not all CPUs have configurable TDPs.
 
interstellar said:
And Intels processers seem to be way over their promised TDP:
Click to expand...
Says who?

You realize your chart above is for the entire system, right? So those values for that 9900K, for example, also include the power consumed by the motherboard, the M.2SSD, 4 x 8GB of RAM, a 1080 Ti graphics card, H115i GTX cooler, the PSU's own inefficiencies, and whatever case fans where used too.
 
interstellar said:
Hi,

When looking at power consumtiopn charts for newer CPU's in Desktop computers such as I7 / I9 and Ryzen 3000
I'm surprised just how much power they consume these days even at IDLE (all the cores and threads). And Intels processers seem to be way over their promised TDP:
It's nice to have a powereffecient laptop (it feels like a waste to use a powerhungry Desktop for browsing the web and writing) for most of the daily tasks, but of course if you need a desktop for
heavy video editing or gaming you would need to build a Good desktop. So my question is this
Which CPU would you go for today if you were to build a desktop that colud do medium photo editing / 4K video editing: Ryzen or intel? Which generation and model?
Are there safe methods to limit the TDP or power draw? Are there smart ways to regulate GPU and CPU power draw these days fx at idle?

View attachment 134347

Link to power consumption thread
wccftech.com

Intel Core i9-9900K 8 Core and 16 Thread 5.0 GHz CPU Review Ft. Z390 AORUS Master Motherboard

Intel has released their 9th Generation Core family and today, I'll be taking a lookg at their Core i9-9900K CPU onthe AORUS Z390 Master.
wccftech.com wccftech.com
Click to expand...

You know that chart isn't CPU power consumption, right?
 
Outside of the miss on the chart, it has long been known that both Intel and AMD's TDP values are not what they seem to be for CPUs.

interstellar said:
Which CPU would you go for today if you were to build a desktop that colud do medium photo editing / 4K video editing: Ryzen or intel? Which generation and model?
Click to expand...
A simple 3800X and X570 system would work out well...
 
I will just leave it here:
 
Plus at the end of the day the end user controls power use, and it's rasily done , using windows own controls the CPU's performance can be regulated, i crunch on my 3800X but not at full clock i set it to 3.5Ghz by turning down the max allowed processor load in the power save profile with hibernate disabled for a nice power saving.
 
That marketing value as TDP you have to read about, because its not a direct power consumption value. Both manufacturer describe it how they 'count' or 'mean' it. Probably you know already its different interpretation for both side.

Usually in your motherboard bios you can set it. (I can in my gigabyte boards on s1155, msi fm2 too)
Look for power current or similar setting.
 
Most desktop PCs aren't particularly efficient since they operate at high voltages and frequencies. If you want to have maximum efficiency you will be looking towards a lot of the server (eypc and xeon) parts, preferably with the higher core counts. A larger processor going slower will use less power than a smaller processor going fast for the same amount of processing done.

This difference between consumer and server parts is because most consumers don't particularly care about energy per calculation efficiency, while in servers that is a large part of your overall cost.

Like others said, basically all consumer/enthusiast platforms have configurable TDPs. In cases with voltages and/or multipliers unlocked you can also undervolt and downclock for better efficiency.

As far as hardware goes, the most efficient CPUs at the top end of performance right now are probably going to be the 48 or 64 core epyc chips.
 
interstellar said:
So my question is this:
1)Which CPU would you go for today if you were to build a desktop that colud do medium photo editing / 4K video editing: Ryzen or intel?
Which generation and model?
2)Are there safe methods to limit the TDP or power draw?
3)Are there smart ways to regulate GPU and CPU power draw these days fx at idle?
Click to expand...

1) Have both Ryzen 2700X and Intel 8700K - Love em both.
2) Yes there are safe methods to limit TDP. = Manually configure a lower clock and voltage used.
3) See answer #2, can always run a desktop cpu more efficiently. It just so happens most people (enthusiasts/gamers) like to overclock instead....
 
GorbazTheDragon said:
Most desktop PCs aren't particularly efficient since they operate at high voltages and frequencies. If you want to have maximum efficiency you will be looking towards a lot of the server (eypc and xeon) parts, preferably with the higher core counts. A larger processor going slower will use less power than a smaller processor going fast for the same amount of processing done.

This difference between consumer and server parts is because most consumers don't particularly care about energy per calculation efficiency, while in servers that is a large part of your overall cost.

Like others said, basically all consumer/enthusiast platforms have configurable TDPs. In cases with voltages and/or multipliers unlocked you can also undervolt and downclock for better efficiency.

As far as hardware goes, the most efficient CPUs at the top end of performance right now are probably going to be the 48 or 64 core epyc chips.
Click to expand...

That's inteteresting so the Intel X /xeon series has a lower power consumption than most i5, i7, I9 at IDL and has more cores and Threads.
The ideal scenario would be to have a PC that uses 20-40Watt max at IDLE, and then ramps up to 200-3000Watt during video editing or photoshop.
The Xeon are a bit more expensive so maybe my best option - for a potential future build- would be to get a used Xeon and a motherboard that uses little power and perhaps a GPU where it goes into sleep mode during idle or something like that.

It's nice to know that There are configurable TDP options, I will look into that for the CPU that suits my need.

Tbill_Bright: Yes, now i realized it lol - I was guilty of being a little too fast! Thank you for the clarification :P
 
The fact of the matter is, if you don't build a huge gaming rig, with a huge gaming GPU and a bunch of other RGB accessory garbage. You can leave desktop processors pretty much stock and get good power efficiency. They already pretty much do exactly what you want, idle down to 20-40w and go higher when under load.

My i5-9400 rig idles at 8w, yes 8w. And thats with the WiFi card enabled, but not connected just scanning for available networks. I could probably cut another 1w off if I just disabled the WiFi card.

Under full load, running Cinebench, it goes up to 84w. Yes, that is higher than the rated TDP. But that is how modern turbo boost works on CPUs and GPUs. Also, TDP isn't how much power the CPU will use under full load, it is a envelope or range of how much heat the CPU will produce. From what I've gathered, it will be how much heat the CPU will product at its base clock. But, again, this is full load, something most PCs don't really see that often.

Browsing the web with Chrome and watching a 1080p Youtube video has the power bounce around between 12w(when just the youtube video is playing) to 35w when pages are loading in chrome. It will even very briefly spike to 60-80w, but it is very quick that it does that.

There is no need to look at a Xeon or anything like that to get power efficiency. In fact, in my experience, they aren't really any more power efficient. Except for the ones that don't have an iGPU, because obviously they don't have to power an iGPU. But then you're making up for it by putting in a GPU that likely consumes more power than the iGPU would... But the fact is, even desktop processors will be power efficient, they'll idle down to use almost no power, just like laptop CPUs and they'll speed up when needed to complete the work asked of them. They don't just sit there sucking down power full blast all the time, both Intel and AMD have done a very good job at power efficiency.

So, the question of what CPU would I pick for medium photo edition / 4k video editing? Well, those are two very different things, aren't they?

Medium photo editing, heck heavy photo editing, can be done with an i3. You'd be fine with an i3-9100, but at that price point you're also looking at an R7 2700 on the AMD side. The 2700 is hard to pass up in that situation.

On the other hand 4k video editing is a completely different beast from photo editing, and need way more CPU horsepower, and a halfway decent GPU helps here too(while a GPU wouldn't really help with photo editing). On top of that you need the storage that can support 4k video editing, but that's a different discussion. Let's just focus on the processing part of it here. For 4k video editing, you'll need the best CPU you can afford. That's all it comes down to. But even if you get something like an i9-9900 or i7-9700 or a 3900X, they will all idle at very low power usage. I'd bet they all would idle at under 20w. Probably not the whole system, especially if you have a GPU, but the processors themselves would all idle below 20w power usage, and heck probably close to 10w. The next concern will be the GPU. If you get something mid-range, that too and idle pretty darn low. Going with something in the 1660 to 2060 range will help accelerate 4K video editing, but also not consume insane amounts of power. The 1660 idles at like 6w and the 2060 idles at like 9w. So with the GPU, you're still likely going to be idling in the 20-40w range, I would guess closer to 20w than 40w actually.
 
I admit, I did not sit through the whole 38 minutes of that video. Pretty sure it would have just wasted about 37 minutes of my time.

CPUs rarely sit at maximum utilization for long periods of time. In fact, most of the time, they sit closer to idle than maxed out. And as newtekie1 pointed at, at idle, they burn less than many night-lights.

GPUs are often the most power hungry devices in our computers. If not the most, certainly the 2nd most. And they are not maxed out most of the time either.

RAM, when not idle, can get hungry.

Drives, fans, motherboards, USB devices all consume power. Even the least efficient devices in our computers, the power supply, eats up power - often lots of it.

So even if you game hard for 8 hours straight, for most of that 8 hours, power consumption is not anywhere near maximum.

If wasting energy is a concern (and it should be) make sure you turn off the lights and TV when you leave the room. Know what you want in the refrigerator BEFORE opening the door. Set the thermostat a couple degrees higher in the summer and lower in the winter. Caulk around your windows and doors. Keep the garage door closed.
 
Bill_Bright said:
I admit, I did not sit through the whole 38 minutes of that video. Pretty sure it would have just wasted about 37 minutes of my time.

CPUs rarely sit at maximum utilization for long periods of time. In fact, most of the time, they sit closer to idle than maxed out. And as newtekie1 pointed at, at idle, they burn less than many night-lights.

GPUs are often the most power hungry devices in our computers. If not the most, certainly the 2nd most. And they are not maxed out most of the time either.

RAM, when not idle, can get hungry.

Drives, fans, motherboards, USB devices all consume power. Even the least efficient devices in our computers, the power supply, eats up power - often lots of it.

So even if you game hard for 8 hours straight, for most of that 8 hours, power consumption is not anywhere near maximum.

If wasting energy is a concern (and it should be) make sure you turn off the lights and TV when you leave the room. Know what you want in the refrigerator BEFORE opening the door. Set the thermostat a couple degrees higher in the summer and lower in the winter. Caulk around your windows and doors. Keep the garage door closed.
Click to expand...

And if you don't have LED lights get some as lights are the things that burn the most energy in our homes. One 100 watt light bulb pulls a 1000 Watts of power every 10 hours. Now imagine if you have a 25 of them around your home.
 
i'll say...
1- ITX Build with a AMD 3400G APU(+ Undervolt), 3466+ Mhz Ram, All solid state Storage, 80Gold/+ Rated PSU(450w Max).
You get 8 Threads and a good Vega GPU for light gaming and editing, very very good perf/watt. I really really like this config i must say.

2- ITX Build with a AMD 3700x CPU, an efficient midrange GPU(something like a 1660,2060), All solid state Storage, 80Gold/+ Rated PSU(450w Max).
16 Threads, dedicated GPU, way more powerful but consuming a bit more.

I have an undervolted (using a negative offset) Ryzen 1700, 16GB GSkill 3333Mhz@CL14, Biostar X370 GTN, Sata SSD + Sata HDD, Vega 64 Reference (1425 Core, 1075HBM2), 80Gold 450w PSU, 3x120mm fans. Idle power is 45-47w at the wall. Amazing i must say.
 
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EarthDog said:
Is that just the CPU? Wondering how the motherboard and such manages this while idle but not 'sleep'. What is showing you this information?
Click to expand...

That is the entire computer. Measured with a Kill-A-Watt and confirmed with my UPS software. This is power consumption at the wall, and the power supply isn't even 80+ rated AFAIK.
 
generaleramon said:
i'll say...
1- ITX Build with a AMD 3400G APU(+ Undervolt), 3466+ Mhz Ram, All solid state Storage, 80Gold/+ Rated PSU(450w Max).
You get 8 Threads and a good Vega GPU for light gaming and editing, very very good perf/watt. I really really like this config i must say.

2- ITX Build with a AMD 3700x CPU, an efficient midrange GPU(something like a 1660,2060), All solid state Storage, 80Gold/+ Rated PSU(450w Max).
16 Threads, dedicated GPU, way more powerful but consuming a bit more.

I have an undervolted (using a negative offset) Ryzen 1700, 16GB GSkill 3333Mhz@CL14, Biostar X370 GTN, Sata SSD + Sata HDD, Vega 64 Reference (1425 Core, 1075HBM2), 80Gold 450w PSU, 3x120mm fans. Idle power is 45-47w at the wall. Amazing i must say.
Click to expand...

Thank you for sharing these setups, it's nice to see some actualy examples of what a power effecient machine would look like !
Does using a 400W power supply draw less power than using an 800W power supply? What if your GPU and CPU need more power than the power supply can supply?

Bill_Bright: If ram consume much power when under load, would it then not be smarter
to have more Ram than nessecery fx 16Gb instead of 8Gb? Then they don't get as "strained"

So to save power on computer
1. Get ITX motherboard
2. Platinum PSU 80+
3. Undervolt your CPU / TDP configuration (it's not dangerous?) what if you run a heavy program and the CPU is undervolted? what would happen?
4. get SSD
5. Good Cooling (effecient Coolers)
6. Connect a power plug to your neighbors AC and run the wire to your own home (this saves 100% of your Power)

Anything else?
 
Real data not to hard to find ... and from reliable sources. For example.

www.techpowerup.com

AMD Ryzen 9 3900X Review

The flagship of AMD's new Ryzen 3000 lineup is the Ryzen 9 3900X, which is a 12-core, 24-thread monster. Never before have we seen such power on a desktop platform. Priced at $500, this processor is very strong competition for Intel's Core i9-9900, which only has eight cores.
www.techpowerup.com www.techpowerup.com

If concerned about power, pick a PSU substantially large than your power needs. PSUs hit peak efficiency at 50% of rated load. So yes, if you are using 400 ~ 425 watts, an 850 watter would be a better option than a 450 watter. But low power and best efficiency are two very different things.

Better yet, use a laptop ... and a K-tor Power Box 20 Watt Pedal Generator for you and a few friends.
 
interstellar said:
Thank you for sharing these setups, it's nice to see some actualy examples of what a power effecient machine would look like !
Does using a 400W power supply draw less power than using an 800W power supply? What if your GPU and CPU need more power than the power supply can supply?
Click to expand...

No a 400w does not draw less power than an 800w PSU. This depends on the demands of the system and also efficiency of the PSU itself.

No it's not 400w sustained. That's a peak watt advertisement.
80% of 400w loaded for a period of time. This is what you should base your PSU purchase around.

So on a 400w Peak, 80% load is only 320w which you could safely sustain.
You don't want to run a PSU at it's peak for a sustained period of time.

If your PSU is too small, 2 things happen.
1. system won't turn on.
2. system shuts off under a load.

Yea, I get shunned for running 850w PSU. "it's way overkill" they say. "you wasted money" they say.
Well, I've had it for 9 years on many many systems now. It still spanks 550w (peak) corsair PSUs all day lol.
 
John Naylor said:
If concerned about power, pick a PSU substantially large than your power needs. PSUs hit peak efficiency at 50% of rated load. So yes, if you are using 400 ~ 425 watts, an 850 watter would be a better option than a 450 watter. But low power and best efficiency are two very different things.
Click to expand...
Good power supplies have fairly flat efficiency curves. You'll end up spending more money buying this powerful psu than you will ever save having a potential few % increase in efficiency.
It's time for this 50% load golden zone to go away.
Not to mention that most PCs spend most of their time in idle or at least in low energy consumption mode.

People are too obsessed with power saving these days, to the point they pay premium for the privilege of doing it.
 
Most users in forums like this are gamers and overclockers.
These types of people will always inquire load based situations because they tend to actually load the system.

Click @newtekie1 system specs above. The build was done right.
8700k 1080ti. Liquid cooling, fans the ball of wax. He's Smart, 850w psu. He can load that to 600w load sustained. Easily run SLI.

Psu and power saving. = Buys Ryzen Athlon 220ge uses igp and can use nice small psu.

Gaming and OC.... Go big or stay home.

Will a 650w peak suffice most single card gaming rigs? Sure why not? Would you build the system to fully pull 650w and still call it good? I think not.

People arent "saving power" building gaming rigs.
Save power with gaming rig? Game less lol.
 
80plus gold is fine, you don't need platinum. Do your research first, some psu's are better than others from same manufacturer so buyer beware, always check reviews, I recommend to buy at least 250watts more than you need for future upgrades. Just because you buy an 800watt psu doesn't mean it'll be pulling 800watts all the time (unless it's a crap psu).

Also, underclocking doesn't necessarily save money.
 
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The most common misunderstandings about PSUs:

A Gold rated PSU is always better quality than a Bronze rated PSU.

Using PSU wattage calculators on the net or recommendations from card manufacturers is the way to calculate what wattage you need for your rig.

A gold rated 600 watt PSU at maximum efficiency can only deliver 520 watts because it's only 87% efficient at full load.

Spending extra for a Platinum or Titanium PSU will pay for itself for everyone in the long run from saved electricity costs on the utility bill.
 
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