Comment by Hoh6quee | Hacker News Reader

Comment by Hoh6quee | Hacker News Reader

Well, I can certainly provide an argument against expectations of long term usage as well.

I bought a pinebook pro, perfectly knowing the performances limitations this article discusses, and actually _wanting_ to learn to live with a less powerful computer, consuming less electricity. In a era where we're roasting Earth, this sounded almost like a duty to me.

But when I received the computer, I had a blocking problem with it : its SD card reader was faulty and would trigger I/O errors after a few writes, and the OS would remount the device as read-only. This is a major problem on that computer because it has very low internal storage space so you're supposed to use a SD card to hold data. I tried various OS, various SD cards, did my due diligence to confirm it was a hardware problem - it was.

I wasn't that annoyed at that point because pine64 sells spare parts on their web shop. So I went there to replace the SD card reader, which meant replacing the main board as well, but OK. This was all very fairly priced, so no problem. Except… the spare part was out of stock. So I waited a few weeks, and it was still out of stock.

I mailed their support presenting my problem and asking a simple question : will spare parts will ever be available again?

They answered by asking me to demonstrate this was a hardware issue, which I did. They did not answer my question, so I asked it again, telling them that I was not wishing to make the device travel the world and back, I just wanted to replace the faulty part. They answered me with the address were I should ship the computer to them. So I asked them again directly : will the spare parts will ever be available again? They dodged the question once again and asked me to send them the computer.

I guess asking to ship them a faulty product is totally fair, they want to inspect it. I'm not willing do to that because we fly way enough products around the world as is, and I can do any check they want me to do locally. But fair enough, they want it back to solve my problem.

What troubles me, though, and what is relevant here is that while they advertise selling spare parts for their computer, they actually don't, and they're shady when asked if they will again. Which probably means they won't. So yeah, I wouldn't bet on long term usage if you have an experimental device that you can't repair.

I think it's because they're all English-as-second-language support staff. I've had the same issues as you and ultimately gave up trying to send them money for spare parts they offered because we kept talking over each other.

It could be. I would say it's unlikely, given they had no problem handling a technical discussion when asking me to demonstrate it was a hardware problem (it was done in several mails, during which they asked relevant questions after each of my mails). I guess it may have been handled by a different team, though, sending the ticket back when confident it was indeed related to hardware.

I've had similar issues with their support and only managed to have the issues resolved this week, almost two months after receiving the device.

The only answer regarding replacement parts that I've gotten from them was that they're waiting for the manufacturer, they never provided any indication when they themselves were expecting the next shipment from their manufacturers.

Thanks for letting us know. Hopefully, this is just terrible communication on their part and we will see spare parts again.

Unrelated to your hardware troubles, but I think it's relevant to mention that the pinebook pro probably uses about the same amount of electricity as a (contemporary) Intel/AMD laptop.

The data I've found from some quick googling [1] indicates a power consumption of around 5 watts at idle, with the LCD backlight dimmed to 40 percent brightness, with power ranging from there up to about 12-15 watts at load.

From experience, the 13 inch Intel laptops I've used recently burn about the same at idle, and don't consume much more for basic tasks, especially e.g. hardware accelerated video decoding.

The other thing to consider is that they're much faster than the pinebook while consuming equal amounts of power, therefore using less electricity overall since you're waiting less time for the CPU to idle down (assuming you're not pegging the CPU at full load, which is harder and harder to avoid with JavaScript event loops running everywhere...)

All that to say, a slower/worse computer =/= a more energy efficient one. Although it probably does build the "software discipline" you need to use energy efficient software ;)

[1] https://gist.github.com/ayufan/1075c3c48ad3e9c7928334c99f7b3...

FWIW I'm regularly able to get ~12 hours on a charge on my PBP with normal terminal and qutebrowser or epiphany sessions running. That's closer to 3W under load, not 5W at idle.

Also, while power usage does go up a bit when the CPU is more fully loaded, it definitely doesn't jump up to 30+ watts like my ThinkPad does.

The Rockchip SoC in the PBP isn't impressive compared to the ARM chips going in current-gen high-end smartphones, but the max TDP isn't anywhere near what an Intel or AMD laptop chip cranks up to.

That also means a truly fanless computer with a monolithic, user-replaceable battery.

There's are certainly workloads where a faster, symmetric multicore x86 chip will win on computer per watt, but it's not as cut-and-dry a win in real-world usage on a laptop as it might be on (say) a heavily-loaded server.

So, this got me curious. I pulled up my now 5 year old Skylake dell laptop, and did some quick measurements.

The "pure idle" draw is around 2.47 watts drawn from the battery with the brightness set to half.

When watching a 1080p youtube video fullscreened, the power consumption levels out at around 5 watts, again at half brightness.

If your workload is very light, there won't be much of a difference. Running mostly terminal emulators and lightweight desktop software, your biggest power consumer will likely be the screen, and most LCDs will be similar.

But if you're running heavy software like Slack or Teams (which some don't have the option to avoid, sadly), then power-per-watt becomes relevant, as running your 30 watt system for 0.5 seconds uses fewer joules of energy than pushing your 5 watt system for 4 seconds.

The rub is that a lot of that heavy software will eat up as many system cycles as the OS will give it -- which annoyingly means that once you have a bunch of tabs open in a browser, that 30 watt processor will probably stay nailed at its TDP.

However, you can manually set limits on the CPU. If I limit this skylake's max clock to 900MHz, I can play Minecraft at slightly reduced settings pretty smoothly while only drawing 7-8 watts.

It's all in what you need. If your primary goal is to reduce electricity usage, "cpupower frequency-set --max <x>" your CPU down to its lowest clock, and you're set.

(none of this is meant to diss Pine64 or ARM -- only I think getting one to be eco friendly/power efficient may be misguided, depending on your use case)

Hi,

thanks for your input, it's greatly appreciated. I'm quite new to considering my power consumption, so indeed I may still do naive choices. I only based it on the reputation of ARM for being more energy efficient, and the observation that ARM devices indeed run longer with a full battery charge (but there may indeed be a lot of secondary variables explaining it).

I'm curious : how do you measure the consumption of electricity in watts? Is there a tool meant for that?

Looking back, I was being a bit too cynical and dismissive. There are of course other factors in a device being eco-friendly, and in practice hotter chips will tend to use more power unless restrained.

On my intel laptops, I used "powertop" to measure power consumption as reported by the battery. Powertop is an intel specific tool, but I think most batteries will have an entry in linux's sysfs. Here it's under "/sys/class/power_supply/BAT0", where two files "voltage_now" and "current_now" list the voltage and current in microvolts and microamperes.

  [eery@darkshire ~]$ cd /sys/class/power_supply/BAT0
  [eery@darkshire BAT0]$ cat current_now
  269000
  [eery@darkshire BAT0]$ cat voltage_now
  8423000

So 269,000 µA x 8,423,000 µV is about 2.266 watts.

Measuring while connected to mains/AC power will probably need some kind of physical device to measure the current being pulled by the charger, sadly. Only server grade hardware seem to have built in current meters :(

Actually, you're better off with a modern AMD processor and artificially throttling it to a lower TDP. Or you can go with Ryzen APUs that are available for laptops with TDPs as low as 15W for 8 cores. The secret is that the all core frequency is 1.8GHz.

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