Busting 8 Common Homelab Power Efficiency Myths

The first 200 of you will get 20% off Brilliant’s annual premium subscription.

Follow me:

Support the channel:

Videos are edited with Davinci Resolve Studio. I use Affinity Photo for thumbnails and Ableton Live for audio editing.

Video gear:

Other stuff that I use:

As an Amazon Associate, I earn from qualifying purchases

Timestamps:
00:00 Introduction
01:34 Myth #1 – Idle power draw is meaningless
03:59 Myth #2 – The lower the TDP, the lower the idle power draw
05:45 Myth #3 – Undervolting can decrease idle power draw
06:47 Myth #4 – ARM is more efficient at idle
09:37 Myth #5 – Newer = more power efficient
11:39 Myth #6 – Laptops draw less power than desktops
15:24 Myths #7 and #8 – PSU-related myths
18:42 Outro

[WolfgangsChannel]

The first 200 of you will get 20% off Brilliant’s annual premium subscription.

[koobluh]

As a low power enthusiast who runs my homeserver 100% off a solar panel, I have to admit myth #5 tripped me up. I knew all the rest though!

[ChristopherHailey]

The information efficiency of this video is incredibly high. Seriously this is one of the best myth v reality videos I've seen. I've been working with servers and home servers for quite a while and I picked up some really useful info here. Wolfgang is putting out some great content on this channel

[Zanthum]

"Myth#4 ECC..."
"NO. we're no doing that today"
😂😂😂

[chod]

small form factor hp (and other) office machines are great entry points. they are (usually) engineered well for power efficiency and can be picked up cheap.

[SystemErrorMessage]

i'd like to mention one thing you could mention. When it comes to CPU power efficiency generation does matter for idle loads combined with the motherboard, software and bios features. Turning off audio can save 1W (measured at wall) in bios. When the PC is in bios it consumes a lot more power than when it has booted into an OS.
I tried turbo stat on 3 PCs. 1 a low end amd ryzen dell, 1 a 1U erying PC, and 1 an old haswell in a high end motherboard. Tweaking the erying is a nightmare but the erying has aggressive clocks, so the idle is between 1.6-2+W. the amd ryzen had a consistent 1.6W idle while the haswell showed around 20W. I have the haswell tuned with power efficiency options available and i have a wattmeter running at the wall for my cluster, showing 100+ watts including the switch. I've measured each computer individually.

The biggest issue no one talks about in power draw which your video does not address is the GPU. GPU idle is a huge pain and is why i dont run GPUs in servers. If you have a program idling in the GPU it will for sure not idle at its rated idle, but even then thats still a significant increase because consumer dedicated GPUs do not shut themselves off when unused like with nvidia optimus. Sadly even this option isnt available for linux. I am trying to use openCL and other features on GPUs so the IGP is good but once i start using the IGP in my own software, the idle power consumption will go up for sure.

Many do not configure their bios for power efficiency but not all bios has the options and not all motherboards draw the same power as it depends on their VRM designs and how much hardware is packed on the motherboard. things like optical, multiple NICs, more sata ports even PCIe can actually increase power draw depending on what is added to introduce it. Fans for me can consume 20-30W alone.

[sebastianrasor]

Always a great day when Wolfgang uploads

[mytech]

Storage drives are also a significant power demand. Even older spinning disks can be set with different sleep profiles from constantly spinning for low latency to fully parking the heads and disk when idle for more than a few seconds. It is a difference of around 8w per disk from parked to a continuous write, so a 4 disk array will take ~10w parked swinging up to 40w when writing.
Storage consumes more than 50% of the total energy used my NAS, which idles at 4w and peaks at 15w with one 5400rpm 3.5" disk. A second disk and it's up to 6w and 20-22w.
It has fairly low computing power and was manufactured specifically for the file serving task. (Single core ARMv7 SOC at 1.2GHz and 128MB ram, just enough to feed files on 1Gb ethernet and do some minor services like DHCP, local DNS and background torrents.)

[shapelessed]

"ECC Is a must have" - Man. I can tell you from experience... Your server is 1000x more likely to screw something up because of a small mistake made by a developer behind some library, used by another library, used by a yet another library used by some small background service running on your OS than a cosmic ray flipping a bit in your memory.
How do i know that? - I am that developer.

[fabstems]

istg every time this man does a sponsor segue he always catches me off guard, "computer science and math doesn't have to be boring"
and I'm staring at my screen like, "Yeah it isn't, but why does that-"
"Well here's the sponsor of todays video, brilliant!"
"Damn it! He got me again!"

[recnas]

Well done! Thanks for mentioning #5. Many people won't believe you can build low power systems even from 20+ year old parts. Although #2, #3 and #6 do play a more important role with less sophisticated power saving features in older hardware.

[aetch]

A couple of extra thoughts regarding PSUs:-
1). Personally I found that the more powerful the PSU the higher its idle draw power.
2). A server with lots of hard drives will need a larger number of SATA power connectors, which can exclude some lower power PSUs. I found that SATA/Molex power splitters are dodgy at best and something to be avoided if possible.

[calyodelphi]

Definitely liked watching this video! It makes me feel glad that I'm not deluding myself into thinking I don't HAVE to use a RasPi or go hunting around for The Most Efficient Hardware to run a home server. I can just use what I've got or build what I need and not worry so much about the power efficiency! 😄

[mikeydk]

Still using an old 4790k for my server. Having quick sync build in, is really handy. For an update, I would want one with AV1 and H.265 support. Having 2x SSD and 5x 5.25" harddisks, running a handful of dockers and two VM's (one of them being a windows), power draw is 65w-120w, depending on what it is doing.

[layplay]

Me watching this with my 10yo server idling at 110W be like: 👀

[eliptikon]

One thought concering power usage: If I have a beefier CPU, I can do task faster then with a low tier CPU, even if they draw the same amount of power in idle. So it makes sense to go with a mid-range CPU depending on the usual tasks you do.

[otter-pro]

great video as always. My file backkup server is based on Intel G2030 2c/2t 55w tdp cpu from 2013 ($35 total from ebay, except for hdd), and is pretty much all I need. It powers on automatically only when needed and turns itself off when it finishes making backup job, so I don't worry too much about power consumption.

[Guishan_Lingyou]

As a person just starting to consider building some home network/server stuff, this information is very helpful.

[lukas_ls]

What often gets overlooked about ARM CPUs is that they're usually more efficient because they're more customizable. What contributes way more to power usage than the CPU itself are the features and I/O (nowadays I/O is the most significant factor in power consumption. Moving data is typically way more expensive than calculating it).
ARM allows their customers to custom build CPUs. AMD and intel on the other hand have one architecture (they do have multiple) that must serve multiple applications. ARM systems are often more purpose built which make them way more efficient. Good examples are the A64FX (designed for the Fugaku supercomputer) and the Ampere Altra line. They're both based on basically the same CPU cores (the A64FX's became N1) but have different feature sets. The A64FX is designed for maximum 64bit floating point compute (and it still outperforms most modern CPUs at that) and maximum memory bandwidth (it's basically a more general purpose GPU) and doesn't need much memory or many I/O Lanes. The Altra on the other hand doesn't have HBM Memory support, lacks the SVE (vector compute for FP compute) extensions but has way more I/O and great integer performance.
Unfortunately, most reviewers don't see that as an advantage and tend to point out that certain ARM systems are not so great at every single task (even though they perform well at what they're designed to do).

[JavierPerez-fqfi]

Great non typical content Wolfgang! Thanks for sharing your knowledge and expertise