So with an update (not sure anyone is reading this), the T520 for $44 is going strong with ubuntu -> docker -> Home Assistant and node-red. The m.2 hasn't been a limit yet.
I bought it from
here (ebay), I don't recommend the stand. A laptop cooler or nothing would be better. Also, the 16gb is fine if this is a pi replacement, but if you go for Emulation Station or something, you may want a better m.2 ssd. Or keep a USB drive attached with roms. Without stand or SSD, it's $28 with the power supply included
Well, sometimes it's not really about spending the least amount of money as much as getting the best bang for your buck (so to speak). For example - I recently put up an eBay best-offer for a t520 with 8GB RAM, 64GB SSD, 802.11ac+Bluetooth, a warranty that's still good until the end of the year, and a Windows 10 IoT license (the model # is V2V48UT).
How much did I spend?
The seller accepted 35 USD, plus 15 shipping, and about 4.75 USD in taxes (which disqualifies it from the
50 dollar cheap server project that I am writing up). For about 55 USD, it's a bump-up from the 35 I spent on the t420. I was supposed to do a t520 writeup on the resources but I didn't have the bandwidth to do so lately, but in general it's an okay little box...a little long in the tooth (it's a 2014 machine in the same vintage as a t620 Plus), but the memory controller on the SoC can support up to 16GB DDR3 SODIMM per socket, so if you need that much RAM, you can totally max it out (although I seriously question the wisdom of spending 130 USD on dead-end RAM tech to max out a 55 USD machine). And yes, I tested it out with one of the 16GB SODIMMs from my maxed out t730 - and yes, it works just fine. The t420 is more of a mental exercise - what can you do with a 40 dollar x64 machine? Can
Nick Fusco use it instead of the EliteDesk 705G3 on the pfsense article? Probably...even the gimpy little AMD APU will work just as well (if not better than) the MIPS32 or ARMv5 SoCs used in most home routers - probably not enough to route a gigabit connection, but good enough to handle WAN routing for your in-laws.
Then of course, there is the elevator clause in IT purchases - spend a little more and get a better or much better machine. If you gun for the t520,
you can probably get a t630 for about 80 to 90 USD. And if you get a t630, the Ryzen R1505G based t640 was available for about 150 USD up until about 6 weeks ago, and with HP pre-announcing
the t540 (rumored to be AMD Renoir C-series based) and coming out in November, who knows what that'll do for the pricing of those machines out there (it would be funny if the "value" t540 outperforms both the t640 and t740 in the HP lineup).
Repurposing thin clients (the t620 plus being one) are kinda like dealing with the red headed stepchild of Project TinyMiniMicro. Most of those thin clients are even less powerful than the EliteDesk 705G3
@Patrick bought in the beginning of that project, and some are even more restrictive on what you can do with them. The one big advantage they have is how cheap and common they are on the secondary markets.
Cheap little power sipping machines will always have a home somewhere, and the newer thin clients will be with us for a while yet.