As others have said, this needs to be qualified. My HP Elitedesk 800 G2 SFF qualifies as "old" I think, yet it draws 14-15W at idle, measured at the outlet.
It has an i5-6500, 32 GB RAM, 2 SATA SSDs and a 4-port i350 NIC (all ports up). Idle means OpnSense and HomeAssistant running inside KVM on top of whatever kernel version was current in Arch at the time, but with no traffic.
Does the raspberry pi draw 1-3W only? It should be noted that old pcs like these can be had extremely cheap, so the difference in price should take this into account. Moreover, if you need extensions of any kind (NICs, drives), getting them running at all on a PI is somewhat more involved than on a standard PC.
> Gen 8 delivers the idle power much more honestly
What do you mean by this?
> In either case, USFF is an order of magnitude less energy than desktop so it's still a win most of the time.
Doesn't it depend on the actual CPU used? I have an HP Elitedesk Mini (which is basically a small laptop without a screen — the equivalent of the ThinkCentres mentioned in this thread) and the CPU is an i5-8500 IIRC. I don't think this particular configuration would draw much less power than a "regular" desktop / SFF, aside maybe from the RAM (it uses SO-DIMM). I've never bothered to measure its idle power draw, and don't have any comparable "full desktop" to compare.
I don't know if HP or Lenovo have models with laptop-class CPUs in this form factor, but I image that would be an actual improvement on the power draw. I did see however Chinese brands on Amazon sell models with those kinds of CPUs.
Typo in my first sentence about the Gen 8. it should be "Gen 8 cpu's in a USFF appear to deliver lower idle power usage and lower high end power usage than Gen 6/7."
You're correct that some of these machines have desktop CPUs, what I discovered was they also have different classes of desktop CPUs.
The m920q/m920s appear to have differnet power usages an possibly different cpus, or at least they're configured different.
Additionally, if you look up the Gen 6/7/8 power usage for the cpu itself, you can see the idle and total is different as well.
The trick is Lenovo is far from the best priced USFF in this category for the same thing.
When I bought Lenovo, I wanted to try out Proxmox, had no interest in fighting with installation or drivers, an just picked something that had flawless installation... that has since improved with other manufacturers.
The tool from OP here is really cool - I'd probably add some from the spreadsheet I had built out but I haven't had to buy many more of these once I figured it out. Load them up with ram, a few ssds, a UPS and they're pretty solid.
It has an i5-6500, 32 GB RAM, 2 SATA SSDs and a 4-port i350 NIC (all ports up). Idle means OpnSense and HomeAssistant running inside KVM on top of whatever kernel version was current in Arch at the time, but with no traffic.
Does the raspberry pi draw 1-3W only? It should be noted that old pcs like these can be had extremely cheap, so the difference in price should take this into account. Moreover, if you need extensions of any kind (NICs, drives), getting them running at all on a PI is somewhat more involved than on a standard PC.