Unexpected realtime delay error on new Mesa 7i96 install

I'm up for giving any suggestions a try!

Yes, the Mesa 7i96 is connected directly with a patch cable.
Yes, I tried to disable everything I could in the BIOS. There wasn't much to change though!

Most intriguingly, yes, I edited the /etc/network/interfaces file - I can't remember where I read I had to do this, but I'll certainly do as you suggest and try using the Network Manager. And try another cable too.

I'll be back....!

Editing the networks/interfaces file is a proper way to set static IP addresses
and more importantly setup specific driver options like IRQ coalescing to happen
automatically. This is why this method is recommended in the hm2_eth manual page

If you setup a specific interface in the interfaces file, it will no longer be
managed by the GUI (this is a good thing)

If you are getting UDP checksum errors it suggests a hardware fault, I would try a different PC

OK, makes sense. Now you say it, that's where I saw those instructions. I latterly saw the page Tom linked, and as I recall I did the GUI changes too. Sounds like I shouldn't have done the GUI edits. Will they cause me issues, and should I undo them?

I happen to have a second PC like this, so can at least swap the SSD and give it a go....

I doubt the GUI changes do anything if the interfaces file is setup.
At least in Mint, you cannot even invoke the GUI on Ethernet devices
mentioned in the interfaces file

That's useful to know. I deleted the connection I'd made anyway in the GUI.

Just swapped PCs, quickly made the BIOS changes, and ran up LinuxCNC. Alas exactly the same.....

Is there anything else I can try before I ditch these PCs?

Did you change the PC hardware (different PC type?)

No, I had an identical second PC to hand. Was hoping it might be a fault in the first one, but it seems not.

Unfortunately I have no alternate machines I can try, and will have to hit eBay for something suitable.

If you were to offer an educated opinion, would you think I'm best to move on and forget these machines as suitable LinuxCNC candidates? i don't want to waste hours to no avail - but on the other hand, if I need to acquire another machine, it could be the best part of a week before I can get anything. Especially with the way things are right now!

That's unfortunate, Its pretty hard to tell where the problem lies.
Its possible that the 7I96 has a problem but its not something
I have ever seen, If you had the same issue with a different PC
that would be diagnostic.

Fair enough. I'm going to cut my losses and get another PC. I have plans for several CNC projects coming up, so getting something that is dependable to commission things will be useful anyway.

I know you often recommend HP Elite 8300 USDT. I've been looking today and have located a source for such a machine at a reasonable price. It's an i3-2120 based unit. Would that be a safe choice that means I can bypass all the hassle?