I run a small Hadoop cluster for development since it's easier than hassling with one of the shared clusters on the corporate net. This cluster was originally made up of craiglist scavenge, and the weakest node was an old Toshiba laptop. I wanted a better balance, plus a family member could make good use of the laptop. So, when I found a Ryzen 1400 on ebay for $70, I decided to build a new cluster node.
The PSU and GPU were ebay as well, the rest of the parts were bought new. I was originally planning on holding out for an ebay used motherboard, but finding a sucker, er I mean a good price, was taking too long and I figured I was only saving $15 or so anyway. I think I got one of the last US-market $25 M9a's from the newegg cryorig store - I should have ordered two or three! I thought about pulling a 1TB hard drive from another machine, but the rest of the cluster is SSD and I didn't want to slow the node down. (I should probably just pull those hard drives and retire them, I don't even use them for bulk storage any more.) The GT 710 GPU is just something to get video out, but it works perfectly well and the linux nouveau driver doesn't have any trouble with it.
The build was pretty easy because I didn't care about cable management. Had I been aiming for a nicer look, I would have had to remove the motherboard a few times, or do a lot more advance planning, since the cable routing holes in this case are behind the motherboard.
The motherboard ignored all attempts to overclock anything until I did a BIOS reset, and then everything worked. 3000 MT/s XMP profile with no trouble and a 3.6 GHz all-core overclock at 1.25v seems stable with a few hours of prime95. 3.7 crashed right away so I'll stick with 3.6.
(I don't normally run Windows, the reason you see it in the photos is that I'm stress testing.)
(and yes, "frank" is the wee Dell you see in the photo.)
Update: the cluster looks very different these days, see completed build "drac". It's much more capable now.
Update: Stein now has a 1600 CPU to match the rest of the data nodes. The 1400 will find a good home, I'm sure. The 1600 is OC'ed to the same 3.6GHz as the 1400 was.
Not a barn-burner, but very willing and does what I need it to do. 3.6 GHz all-core overclock without a problem, and if I felt like fooling around with it I could probably go a little higher. Current retail price is nonsensical, but at used prices a great value.
This little cooler handles the 65w TDP processor easily, keeping it under 60C even overclocked. Nice and quiet, unbeatable value at its original retail price.
Had to smack the BIOS upside the head with a reset, but then ran fine. Memory is running at 3000 MT/s with no problem at all.
It's cheap, but it's one step up from the $20 top-PSU cases. Not much fun to build in and probably the wrong choice if you care about cable management, but it's moderately sturdy, all the screw holes and mounting points lined up, and I didn't find any finger slicing sharp edges. The funky purple fans are actually kind of cute, and a lot quieter than I expected from a budget case; no annoying whine, just air movement noise. Probably 3 stars on an absolute scale but I'll give it one more for value.
I hadn't planned on putting this good of a PSU into the build, but this one came up on ebay at a decent price. (It was advertised as a Focus but turned out to be a Focus Plus, nice.) Solid and quiet.