I have an old pentium laptop N3520 with 4GB DDR3. I removed everything and put it in a receiver box 1U size. It consumes so little energy that it can run 5-7 hours from its battery (I call it build in USV). Last time I measured 3-7w. Also passiv cooled , no noise. Another machine I use , is with a i7 4770 with 16GB for Proxmox, 7-20w , peak is much higher but rarely used , only on boot and vm startup.

There are also a lot of mini PCs that are comparable in price to a Raspberry Pi 5 once you factor in the cost of a case, SD card, and power supply for the Pi.

Better than an old laptop, get a mini-pc like thinkcentre tiny. They're more upgradeable, space-efficient, power efficient, have better cooling

I wish there was a convenient place to get these

Rockchip boards are way more efficient than Pis

I now have a stack of Thinkpads laying around. Right next to my two RPis 😂

Add use of gpio to reasons to use pie.

While gpio adaptors are available for pc. The software architecture is not as well rounded and documented.

So for any complex hardware project development. Gpio based SBCs are often essential.

So space, low power and gpio development.

Otherwise yep old laptop or even desktop can be cheaper and more able.

But overall. The wide software support and documentation for hardware connectivity is a bloody good reason to keep pie supported.

I'm setting 2 up to control the hot water and solar dump system on my shared little boat. As I want to link 12v Lifepo4 batt charging with the solar dump and visually impaired control for AC and diesel heating of the water.

Pies really are the best option to play with. While low power and easy to design a unique low vision interface.

Some are talking about power consumption in this thread and I've had similar ideas. Gone are the days where I can run a beefy spec'd desktop in good conscience, it's just such a resource hog. I have a laptop that stays in hibernate mostly. My other idea for a low power consumption home computer was to get a Le Potato single board and pair that with an e-ink monitor (there's some really nice ones out there) which I think was sitting at maaaaybe ~5kwh. I think the more we can limit our power consumption, the better, all that electricty directy translates into coal being burned and additional CO2 being created. I'm no luddite, but it has impacted how I consume media which is now very mindful of the impact watching a few episodes/playing a couple hours of games versus just one or two hours of content on any given day.

I use old Mac Minis that were cycled out from a company and replaced. An e-waste laptop is still probably cheaper, but you can still find the older model Mac Minis fairly cheap too. I have 2 of them that sit vertically side-by-side in a small rack with my router stationed above them. They both run Elementary OS.