Hardware advice for 2021

That is a nice machine !
BTW, i do have a Noctua NH-D15 collecting dust ATM. And i have a Creality CR-10S Pro V2 with all fans changed to Noctua 40x20! They are silent for sure, but no one mentions that they move less air as they spin slower.

That is part of the reason I went with the larger tower on that machine even though I didn't need it. Just to have more volume of air available. Yes the Noctura does have lower air velocities, minimizing the turbulent flow is the key for the sound.

I'm going to have to do something fairly quick as I need to have the mill running.

Guys now I am confused so why was I steering in the old PC direction?
Is the setup above with Ryzen going to run LinuxCNC and have no issues with drivers compatibility and have no headache installing it?
I am running MESA 7i95 so don't need any parallel ports at all.
I would rather get new stuff then buy lemon. As i mentioned in another post crashing 2KW servo this time just due to unreliable old hardware is a no go for me.

The above listed parts are on my personal PC that i do NOT use on machines, but it did have a 7i92 connected to it for long periods of time (over a month) and never dropped the link.
As for reliability, i have 3 of HP 8300 running big plasma cutters for over a year, several Dell Optiplex running industrial machines for over ... i don't know exactly, but over 7-10 years for sure, never ever had issues with them. Yesterday had a Dell here as one of the memory banks failed, changed it and it is running perfectly again, since 2010.
So chances are the new one will cr@p out much sooner than the old ones.
Oh and another thing, this is Linux and LinuxCNC, so the Mach3 $hit does not apply here, pressing E-stop will stop the machine if everything is set up properly, inside of 1/1000 of a second. The lag by heavy equipment inertia not included.

No eBay APP ID and/or Cert ID defined in Kunena configurationTommy, does the recommendation of HP8300 SFF extend to the 'ultra slim' version? I'm currently running an rpi4 but keep getting various errors that I'm struggling to fix. I went for the rpi as I'm serverley space constrained but I could accommodate one of these tiny desktops outside of my enclosure. This sort of thing

Right guys I did some searching and I can get these candidates locally. It is easier to get something new then decent old pc.

Dell OptiPlex 3050 SFF  Intel Core i5-7500 3.40 GHz, 16 GB, Intel HD Graphics 630, 500 GB NVMe SSD, DVD-RW

Fujitsu Celsius W550 - *GAME LINE*   Intel Core i7-6700 3.40 GHz, 16 GB, nVIDIA GeForce GT610 1GB, 256 GB SSD + 500 GB HDD, DVD-ROM

HP EliteDesk 800 G2 SSD 240 + 500 HDD 8GB RAM   Intel Core i5-6500 @ 3,2 GHz, 8 GB RAM DDR4, 240 GB SSD + 500 GB HDD, GeForce Palit GT 1030 2 GB

so any good options do you reckon?

No eBay APP ID and/or Cert ID defined in Kunena configurationthis could possibly be another option

Prices?
Last one for 123 Euro, seems OK, but i never had one to test. I did have older ones and they worked.
Just to be on the safe side, there is no guaranties any of those will work properly as i mentioned before, it is a risk, so you have to decide is it worth risking.
I know i would.

123E was the cheapest the once in first post are about 250 - 300E
I still don't know which way to go if I don't want to risk it?
I am not money constraint too much I just need the right machine for the job but do not want to buy HW which will have driver/ compatibility issues. basically don't want to waste money by buying junk I would rather pay 1000E if I end up with no issues.

And I forgot to mention I am running QtDragon I read somewhere that it might have issues to run on older hardware.