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I'm curious if you have measured power at the well (e.g. smart plug with energy metering or Kill-a-watt.) I just set up a test server with a J1900 (10W TDP.) Wi

I'm curious if you have measured power at the well (e.g. smart plug with energy metering or Kill-a-watt.) I just set up a test server with a J1900 (10W TDP.) With 8GB RAM and running from an SSD it uses 25W. Add 4 7200RPM HDDs and it's up to 65W idling. I have another test server based on a Raspberry Pi 4B. The Pi boots from SD card and uses about 5W. Add 2 drives in a USB drive bay and power for the setup is now up to 25W.

heywire 4y ago
This was measured with an old school Kill-a-Watt. When idle, the HDDs spin down. Keep in mind these are 2.5” likely 5400rpm or less (WD Passport 2TB).
j45 4y ago
UPS’ also have this feature and it’s interesting to see the idle vs load wattage. I like the idea of making compute, storage into appliances if possible locally. It’s best to use ssds in the machines. If you want spinning drives put them in a dedicated nas for storage.
PragmaticPulp 4y ago
> I just set up a test server with a J1900 (10W TDP.) With 8GB RAM and running from an SSD it uses 25W. Did you use a regular desktop power supply? PC power supplies can consume 10-15W or more at idle. To build a low power system you need to find a good low power, high efficiency power supply.
- amiga386 4y ago
  Does anyone know a good supplier for such supplies? For 10 years my home server used a Corsair VS350; it was fantastic, and very efficient at low power draw. Recently the fan failed. The PSU seems discontinued. The _fan_ seems discontinued. I'm going to try replacing the fan but I don't know much about electronics. As a temporary measure, I got a regular "gaming PC" PSU and it has 10% more power draw, it's not efficient at all. I've been looking for a replacement PSU, and I can only really find very high power ones - minimum about 550W - for reasonable prices. While you can run a low wattage PC on such PSUs, none of them make very much in the way of efficiency promises; only the highest certification, 80 Plus Titanium, makes efficiency promises for 10% load, e.g. it'll be 90% efficient for a 55W load on a 550W supply. Lower certifications only promise to be e.g. 80% efficient for a 110W load on a 550W supply, and make no promises at all about a 55W or 30W load. So, how does one buy a good low power, high efficiency PSU, without it costing a fortune?
  - suyjuris 4y ago
    > I'm going to try replacing the fan but I don't know much about electronics. Just in case: opening PSUs is dangerous without precautions. The capacitors may retain enough charge to kill. Besides the immediate risk to yourself, a PSU can also pose a fire hazard during operation, e.g. if improperly cooled.
ridgered4 4y ago
2.5" hard disks actually use way less power than the 3.5" drives, but if you spin down the bigger drives they get down to about 1watt. My server at home I actually use a 2.5" drive for the torrent scratch disk since I don't really need speed there I just need something that is always spun up with a moderate amount of space that doesn't use much power.
MayeulC 4y ago
Running powertop --auto-tune and TLP makes a lot of difference on my server (60->30W). You can further tune CPU, disks and GPU to preserve energy. I suggest starting with a laptop or a phone (~postmarketos)instea d,as those are already tuned for low-energy modes, and you won't have, say, a BIOS preventing PCI devices from sleeping (looks at server).

heywire 4y ago

This was measured with an old school Kill-a-Watt. When idle, the HDDs spin down. Keep in mind these are 2.5” likely 5400rpm or less (WD Passport 2TB).

j45 4y ago

UPS’ also have this feature and it’s interesting to see the idle vs load wattage. I like the idea of making compute, storage into appliances if possible locally. It’s best to use ssds in the machines. If you want spinning drives put them in a dedicated nas for storage.

PragmaticPulp 4y ago

> I just set up a test server with a J1900 (10W TDP.) With 8GB RAM and running from an SSD it uses 25W. Did you use a regular desktop power supply? PC power supplies can consume 10-15W or more at idle. To build a low power system you need to find a good low power, high efficiency power supply.

amiga386 4y ago
Does anyone know a good supplier for such supplies? For 10 years my home server used a Corsair VS350; it was fantastic, and very efficient at low power draw. Recently the fan failed. The PSU seems discontinued. The _fan_ seems discontinued. I'm going to try replacing the fan but I don't know much about electronics. As a temporary measure, I got a regular "gaming PC" PSU and it has 10% more power draw, it's not efficient at all. I've been looking for a replacement PSU, and I can only really find very high power ones - minimum about 550W - for reasonable prices. While you can run a low wattage PC on such PSUs, none of them make very much in the way of efficiency promises; only the highest certification, 80 Plus Titanium, makes efficiency promises for 10% load, e.g. it'll be 90% efficient for a 55W load on a 550W supply. Lower certifications only promise to be e.g. 80% efficient for a 110W load on a 550W supply, and make no promises at all about a 55W or 30W load. So, how does one buy a good low power, high efficiency PSU, without it costing a fortune?
- suyjuris 4y ago
  > I'm going to try replacing the fan but I don't know much about electronics. Just in case: opening PSUs is dangerous without precautions. The capacitors may retain enough charge to kill. Besides the immediate risk to yourself, a PSU can also pose a fire hazard during operation, e.g. if improperly cooled.

ridgered4 4y ago

2.5" hard disks actually use way less power than the 3.5" drives, but if you spin down the bigger drives they get down to about 1watt. My server at home I actually use a 2.5" drive for the torrent scratch disk since I don't really need speed there I just need something that is always spun up with a moderate amount of space that doesn't use much power.

MayeulC 4y ago

Running powertop --auto-tune and TLP makes a lot of difference on my server (60->30W). You can further tune CPU, disks and GPU to preserve energy. I suggest starting with a laptop or a phone (~postmarketos)instea d,as those are already tuned for low-energy modes, and you won't have, say, a BIOS preventing PCI devices from sleeping (looks at server).