Recommended PC configuration: CPU and Motherboard (Q1 2020)

Hi all,

As you can see from my very poor post count, I am new to this community and, as it tends to happen to most of the new users, I am overwhelmed by something that, to some of you, might sound trivial. I have been looking around on this forum and other sources, but I still didn't find a satisfactory answer to this question:

What hardware configuration on the pc side would make a good (or very good, even perfect) match for LinuxCNC?

I know, it's broad and rather vague question, so I'll try to expand a bit.
I am at the very beginning of my quest: converting my Mach3 based setup to fully featured LinuxCNC system.

Being at the very beginning means that I do not own any HW I want to integrate and, alack, I have little experience to back me up in deciding where to direct my first steps.

From the very basics: CPU and MoBo.
As I mentioned earlier, I do not have any HW waiting to be used, neither am I emotionally attached to any specific manufacturer.
I will add, I have some budget (so no need to go for the very cheapest solution, unless it turned out to be the most effective), and I don't need the electronics to be overly compact (no need for ITX)
I would just like to start my build with something that won't turn out to be underdimensioned/outdated soon along the path.

One note that might be relevant: I am planning to run my 3 axis machine (3 masters, 4 slaves) in a closed loop configuration.
Two axes need to run on servos, the third could be also stepper (doesn't move much and, when it does, it's rather slow).

So given this scattered set of information, what would CPU+Motherboard would you recommend?

Pietro

That would depend on if you are using the Parallel Port or the Fantastic Mesa gear and whether you want PCI\PCIe or Ethernet Mesa.

I've had some very surprising results with 2nd hand AMD 64 Bit Athlon and Radeon GPU. Should be able to pick a combo for a song, most will have a Parallel Port.

Currently I'm using a J3355B-ITX with a Mesa 7i92/7i76 setup.

Tommy usually has some great recommendations for old Dell gear.

Thanks for the replies! I'm trying to keep the discussion as generic as possible, but there is one specification I should add:
I am writing from Europe (more specifically, Switzerland), as such HW availability can easily become a pain in the neck.

Following up on Tommy's reply: I can easily find the Optiplex series from Dell, but only the new models. Does anything speak against something like this model ?
And does it make sense to buy the full build, or should I rather get the components specs and buy them individually (don't really need the fancy tower etc..)?

BeagleBrainz:
Mesa looks indeed fantastic but, again, I'm concerned about distribution options in my area. Moreover, at work I am surrounded by Beckhoff components: it's still early to state my decision, but I'm definitely looking into possible integrations with linuxCNC ( what looks to be a good starting point )

Forgot to mention: similar situation with fujitsu -> Esprimo P758

It's always surprising how many things one can find with the right research string..
Found an optiplex 9020 (see attached image) for a very reasonable price!

I am not sure I can post here links to resellers (?), but in case someone is interested in knowing where to source used PCs of the "families" we are talking about (in Switzerland), you can send me a pm.

Tommy: thanks for the link, just started reading it and looks like a very good reference.

Talking about the form factor, what is the "usual" approach? I would be tempted to get the largest motherboard for spare PCI ports that might come in handy along the way (I am developing a testing setup and, in my situation, the full requirements are not known beforehand but rather unfold over time), and yet I see most of the people trying to get their hands on the tiniest USFF..
Am I misunderstanding something?

About 300 USD. They have 2 available, if you want...